Electronic Parts Testing Service

Dr Virago Pete's Electronic Parts Testing Service

Send your desoldered components ready for test

1. Desoldered

2. Wrapped carefully

3. Return envelope and postage affixed

Solid state & Semiconductor Components I can Test

1. Transistor

     a. NPN & PNP

     b. Mosfet

     c. IGBT

     d. Power

     e. others

2. Diode

    a. Germanium

    b. Silicon

    c. Zener

3. Capacitor

    a. Capacitance

    b. ESR

4. Inductor

5. IC Chip

    a. TTL Logic Chips

    b. 7400 series chips

    c. 5400 series chips

    d. 4000 series chips / CD4000 series chips

    e. HEF400 series chips

    f. 4500 series chips

    g. ULN series chips

    h. others

6. Voltage Regulator

    a. 7800 series

    c. 7900 series

7. Varistor

8. Optocoupler

9. Solenoid

10. Surface mount components / SMD.

11 Analog Chips

This ad is aimed at the DIY student or hobbyist who is working on his/her own electronic device and needs assistance in troubleshooting.

Consumer-level meters simply do not have the ability to thoroughly test solid state electronics. For example the average multimeter can only test Volts and Ohms.

Intermediate level meters can check capacitance but not ESR. These intermediate level meters can test transistor gain but not leakage. This leads to frustration in the student or DIY repairman/woman because they are looking for a fault they cannot find.

I have professional test equipment which can thoroughly test components you send me for test. Most components on a PCB are soldered in place. You must carefully desolder components before sending them for test. 

Identification of Unmarked components

1. Scratched off markings

2. Worn ratings number

3. IC chips

I am looking for a  "U-TEST-M" vacuum tube tester made by Colonial Merchandising model 2500 and when I purchase one - I will update this ad to include vacuum tube testing service also.

I am looking for a "Linear IC Tester" or "Universal IC Tester" and when I purchase one or more I will add this to my list of chips.

There are many parts I have in stock as replacements and some that I do not have in stock. I also have many books which show the ratings of thousands of parts. I can also cross reference substitutes and replacement parts.

I can identify a replacement/substitute for most parts.

What Makes Dr Virago Pete Qualified?

1. I own many parts checkers and testers

2. 30+ years experience in troubleshooting electronics

3. Former Electronics Instructor

Tips

1. Always put your IC chips in sockets when building a kit

2. If your device runs on batteries - dont run off power adapter

3. Use a correct soldering iron 15watts or less

4. Learn to desolder quickly without overheating your parts.

5. Take a detailed photograph of your PCB and make notes and sketches before desoldering anything from the board.

6. Don't tinker - do it the right way - or don't do it at all

Contact me if you need chips or other electronic components tested. I try to be reasonably priced. Many electronic devices made in the 1970s, 1980s, 1990s, 2000s, 2010s used off-the-shelf stock chips for all or a portion of their functions. I can test these industry-standard parts.

What I'm trying to say is - when you are repairing a device - finding the 1 bad component - whether it is an IC chip or other - you hope that it will be a common part that failed - one that you can easily replace and is readily available. Most likely your device has failed in one or more common parts - cheap to replace - but the trouble is - in identifying which one has failed.

The number one cause of failures in electronic devices is electrolytic capacitors (sometimes obvious due to the bulge) and sometimes tantalum capacitors will spontaneously cease to function or pop/explode - as these can fail quickly - sometimes while letting out a very foul smell unique to a dying tantalum capacitor (several aerospace companies refuse to use tantalum caps in their space missions)

I can test capacitors with my professional ESR tester. Bad capacitors do not always bulge. Sometimes electrolytic capacitors will make a loud POP like a firecracker as it is dead - bulging the top or not bulging the top. Most failures are not dramatic and make no noise or smoke or smell. Equipment is necessary to identify these bad components without visible clues - which is where my expertise comes in.

Dr Virago Pete

(847) 454-7858 between 11am and 7pm daily

email address drviragopete@att.net

Located in Illinois USA

My assistance is not free - reasonable fee - call to inquire.

I use quite a few desoldering methods and decided to add some insights about my Soldering / desoldering equipment. I normally use a Radioo Shack desoldering iron with red bulb for my everyday desoldering of parts, but occasionally I will have a particularly stubborn or delicate part and I am always looking for alternative ways of desoldering parts. 

I have the following Soldering / Desoldering equipment

1. Radio Shack 15/30 watt switchable soldering iron (the one I use the most) 120V I have went through a few tip as they tend to get eaten away by solder and flux. I also use a fine metal file to clean it up when the tip gets nasty. I like when the tip gets short as it heats better. When the tip is new and long it doesnt heat as well as when it is short. I dont often sharpen the tip - only when I have a very delicate soldering job like high-pin-count ICs. The tips unscrew so it is possible to change between semi worn tips and brand new ones. I usually keep a spare tip in my soldering tool box. Previous to this I used a gun handle style soldering iron from Radio Shack approx 30 watts which I liked also but burned out after 10 years of use - not a bad reflection of the mfg at all.

2. Radio Shack 45 watt desoldering iron with red rubber bulb (the one I use the most) this is my second unit as the first one burned out after 15years of regular use which was very reliable and hardworking. 120V I have went through a few tip as they tend to get eaten away by the solder and flux over a long period of years. I usually keep an extra tip in my soldering tool box.

3. Radio Shack Portasol Butane soldering iron - purchased used (tip burned out after 10 years of regular use - I bought an aftermarket brand new in the package Boardworks tip for it (with slots rather than original keyhole shape - and the slotted tip burned out after 1 week of light occasional use) I still have not ordered a replacement original tip as I dont want to keep throwing money at this tip replacement issue - which the tips are expensive. Was very useful for soldering PCB with very large amounts of solder or where high heat is needed - like to reattach coaxial connector on RF shield - where a normal soldering iron just doesnt have the muscle to heat. I like this unit and the burned out tip isnt a bad reflection on the mfg as I got 10 hardworking occasional use years out of that standard tip that it came with. 60watts approx heat output with standard tip. I replaced the flint with a standard Robinson lighter flint as it was worn out from my use and the previous owners use. Update 10/4/16 I have purchased a set of 4ea tips for Portasol and to my amazement - the brand new soldering tip didnt work good after 3-4 soldering sessions - making sooty big flame when lit, sputtering, not glowing red hot, flakey and difficult to get it to work - WELL here is why and how I fixed this issue. See Butane turns into water as a chemical reaction. Over time (my Portasol is over 10years old and used very often - NICE TOOL) there are water droplets/trapped air etc inside the unit. I fixed my unit to much improved but still not perfect condition by using a 1/8" metal rod (Dremel tool end shaft) to push up on the butane fill valve. FFFFFFSSSSSSSFFFFSSSS the butane sprays out the bottom (wear rubber gloves) and this pushed out the water and air. The next time I used the Portasol - it worked and lit much better. I may have to repeat this step to fully get out the contaminants. Dont get me wrong I really like this soldering iron. Its not the fault of the unit or the butane from the hardware store. Butane itself turns into water and collects inside over time - just like a pair of glasses gets condensation coming into the warm from the outside cold winter air. Butane is a gas and gets compressed- when sprays out - it is very cold- thats where the water comes from combustion and also the cold/hot/cold/hot ... condensation.

4. Tenma desoldering tweezers 21-8230 purchased from big-auction site) and I made a few custom-made tips to remove ICs with it. 45watts 120V I like the dual soldering iron design and see my other page for the tips that I custom made for my unit.

http://www.drviragopete.com/ic-desoldering.php

5. Hakko 470 desoldering station with 803 gun (I bought used and doesnt work quite right- temp adjustment even on highest setting doesnt melt some high temp solder but still work fine for normal good type solder but heating could be better - possibly needs adjustment or a weak/worn electronic component inside) This is not a bad reflection of the mfg as it is 20+ years old and Im not the original owner - I have a spare gun and purchased some oddball things it was missing from big-auction-site like solder reservoir spring, and ceramic filters. These little parts are very expensive and I was glad to buy this used unit for a low price on auction- but the little missing/replacement parts pieces add up very quickly in cost. Most electronics enthusiests are nortoriously little-or-no-cost $ spenders. 120V adjustable heat

6. Weller blue adjustable temp Soldering Station WSD80 - in disrepair/disassembled - purchased it that way from an online auction. A restoration project I hope to find time for. It looks like a good unit and the disrepair is not a bad reflection of the Mfg. It is over 15 years old and who knows how much the previous owner used it? My hunch is it is approx 80watts max of heat with the iron I have and is temperature adjustable. I dont know what is wrong with it at this time as it is disassembled and never been plugged in by me.

7. China Imported Blue/White desoldering iron solder sucker 220v 30Watt - never used as it runs on 220v not 110V

Update 5/5/16

I recently purchased a very inexpensive desoldering iron with built-in solder sucker pump (see picture blue/white unit above) and decided to purchase from a California big-auction-site seller. I received the unit in about a week and was just like some of the youtube videos which shows the product. I decided to disassemble the electrical cover just behind the push down lever and I see 2ea bare wires (just like the video) and I also measured the ground aligator clip end and I see no continuity between the hot tip and ac prongs or ground wire - I checked every combination. So the alligator clip ground is non-fuctional. I also spent time researching this item in forums and on youtube videos and there seems to be some confusion on whether this advertised 220V 30W unit works on standard household 120V (as it does have a normal 120V plug) and so I plugged it into my household ac outlet (measures between 123V to 126V AC typically) and the unit does heat up but never sufficiently to melt solder- even after leaving it for an hour. So it gets hot enough to burn your hand but not enough for solder melting on 120V. I was also under the wrong impression by the ad that it runs on normal household ac - but I did see the 220V in the ad also. So to put aside the confusion, I am posting this short article about it. I am still glad to have it even though I have not actually melted any solder with it. It came with a cleaning rod and 2 total tips - one with a fine time and one with a bigger hole. I plan on buying a small travel power adapter which converts 120 to 220 AC to use with this unit. Alternatively, I could disassemble and add nichrome wire in the correct amount to make it standalone 120V but I think I will just buy a cheap small travel adapter as a better solution. Maybe in the future they will make one that runs off of 120V standalone.

You would think that a 220V 30Watt de-soldering iron running on 120V would be a 15watt - BUT NO - it is not like that at all. It simply does not heat sufficiently at 120V. This is not a fault of the mfg but rather a miswording of the advertisement. The only fault of the mfg is the ground alligator clip which is non-functional. Frankly - few soldering irons have a ground wire and are mostly 2-prong. So having a non-fuctional alligator clip leaves me to either snip it off or attach it properly or leave it as-it-is. I havent decided on that part. For now I put it back in its package and will just add it to my close full of electronic gear and parts and stuff- which I use on special occasion. I was planning on using this to fix a particularly stubborn power inverter where the through holes are barely big enough for mosfet legs to squeeze through and they used hard to melt junky solder. I was hoping to find a better desoldering method for these difficult oddball boards - but alas this desoldering pump iron combo wont work on my 120V ac outlet. So until I get a step-up transformer of some sort- I cant actually use it. I only paid a few dollars for it- so Im still glad to have it and someday I may wish I bought a spare - who knows I may find a use for it. No holder was included and it seems to be balanced where if I lay it on the table - the tip doesnt touch the table - but still I will use a small Radioshack bent-piece-of-sheetmetal style soldering iron holder which I already have.

I see that some USA sellers have a "Tenma" model which is Yellow and White - and is probably color coded - Yellow unit for 120V and Blue unit for 220V. So I probably just bought the wrong color. Read the ad because it is possible that the color of the unit does not always match the voltage.

I like to use the bent piece of sheetmetal style soldering iron holder as it has very little contact with the hot iron and so doesnt rob the heat from the iron. I also have a Weller holder and soldering iron which is not functional and I bought it disassembled (previous owner repair attempt?) from a big-auction-site - but have never attempted to repair it - not enough time in a day/funds to get to all projects unfortunately.

I dont leave my soldering irons & desoldering irons running idle - I unplug them when not in use and plug them in just as I need them - letting it warm up for 10-15 minutes before use. This prolongs the heating element life and saves on utility bills cost- that is my personal view and you may disagree - as some people feel leaving electronic equipment like computers on prolongs their life (I disagree) and that the power cycling on/off is what actually shortens the life of equipment. You can have a different view - no problem. I always unplug my electronics when not in use.

Update 5/19/16

After about 10 years of having purchased and not assembling a used Weller WD80 soldering statiion (purchased nonworking and disassembled) I decided to work on it today. I cleaned all the individual parts using a bottle of dilluted green cleaner and water and spray bottle which I used for that cleaning fluid. I noticed that the previous owner boogered up some parts like the digital temp buttons are mashed and solder dings and the case has been exposed to alot of flux over the years and is splotchy- but I cleaned it up and looks better than before but not perfect. The transformer is mounted to the case bottom and plastic had a crack so i switched the ground wires to a screw closer to the the front of the unit which allows the back screw to screw down further and grips the remaining plastic hole and holds the cracked case better. I bent the sheetmetal heatsink away from the board - to a 90degree angle. I used my Capanalyzer to check all the capacitors and I did find one SMD electrolytic which had an ESR of 10 and an adjacent identical which measured 3. But I left it alone. I also checked the diodes SMD style and found none that triggered the ESR meters alarm. I used my Fluke 73 multimeter in diode check mode to check all the diodes and found none shorted and I also checked the 2ea TO220 package devices (possibly transistors- I didnt need to check) for shorts between legs and found no shorts. At that point I reseated all of the clips to make sure good connections. I also removed the fuse from the AC rear plug jack. The fuse tested good removed. I reinserted after bending the fuse holder 2 pins straight as it was a little cockeyed. I used the Fluke meter's continuity check to systematically check the AC prong and input lines to make sure fuse and continuity from AC cord was valid. I powered the unit up disassembled - making sure nothing electrical touched while live. I found that the Weller WD80 does not power up while the soldering iron is not plugged in. When I powered off and connected the soldering iron - then repowered on - then the digital display lit and the soldering iron heated and maintained whatever temp I selected. I carefully bent the heatsink back to straight and reassembled. Later that day I used it to desolder some N-Channel surface mount FETs from a non-working motherboard and tried various heat settings from 500-700.

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Electrolytic Capacitors go bad and are the #1 Cause of Failure

(My Personal View)

Electrolytic Capacitors have a rated lifespan of approx 1000 hours or in the case of highest quality electrolytic capacitors 2000+ hours rated. Multiply 24hours in a day x 30days in a month and you get = 720 hours in one month. So really 90days is the rated life of any device which contains electrolytic capacitors. That is one reason why Manufacturers only offer a 90 day warrnty on TV sets etc- if you leave your TV set on continuously for 90days straight - it will most likely survive 90days without fail- so the mfg is fairly safe offering a 90 day warranty.

It is amazing that so many devices lifespan is greater than 90days - it really is not supposed to last that long. Care in handling and not letting a device get too hot - helps extend the life.

My point is that I always unplug my devices when not in use - any device - especially one where it contains capacitors.

24hours x 30days = 720 hours in a month

3 months x 720 hours = 2160 hours in 3 months

There is some truth to power cycles shortening the lifespan of a device. But I still turn my devices fully off when not in use. Some devices have a standby circuit waiting for a remote control command or a pushbutton command to fully power on- but still a portion of that device is on - even when it is "off" My personal view is - it is better to fully unplug it (or switch off power switch to the outlet or power strip) to prolong the lifespan of the device.

The above is an ESR tester - EDS-88A CapAnalyzer (Series II) which tests ESR (equivalent Series Resistance) for electrolytic capacitors and other types such as tantalum and more. The above file is the user manual. My ESR meter is the EDS-88AII which is a slightly more recent design. The LED bargraph display is easy to read and the alarm sound is settable by the linear potentiometer for sensitivity. The best feature is its automatic self-discharge of capacitors. That was its biggest selling point to me and a big time saver. It will cycle through self-test and several other checks before each and every capacitor check. It is a quick machine and has found countless bad capacitors. An excellent ESR tester.

I already know where the bar graph LEDs should be for small through large capacitors so I dont need to refer to the chart anymore. I just know when the bargraph looks odd for a capacitor then I know it is time to change it. Also comparing the same size capacitor over the same to-be-repaired-board  will make a few stand out as being weak or odd functioning. It is a true in-circuit tester. Some bad capacitors show a led towards the bottom of the bar-graph or dont register at all. Slightly weak capacitors can be just a little higher or lower than should be- those are generally not the cause of a failure in equipment operating. It is the capacitors which deviate drastically that generally are the cause of equipment failure to function etc. I always check my new parts too because there are sometimes duds in brand new capacitors purchased in bulk.

Finding a bad capacitor is not about nit-picking if it is in the red or yellow or green area of the chart. A bad capacitor will be blatently bad. If it is not blatently bad then most likely - that capacitor is not causing your equipment to have failed to work.

A bad capacitor will usually be 2x or 3x or more - the rated esr of the rest of the caps you test which are of similar size/type. It will be blatently bad or will give a no reading or a alarm or be drastically different than the rest of the caps.

Cracked or bulged caps or caps which leak gunk (flux) or fluid (flux) are definitely bad and should be replaced- even if they test fine. Some capacitors are glued by the factory - dont mistake glue for leaking flux.

I dont recommend powering up the tester with the red button held down- this disables the self discharge feature (until next power off) because self-discharge is a protection for your esr tester. Touching a charged capacitor can kill the esr tester. Even though it takes an extra second to automatically discharge.

The tester needs no polarity as it functions with self-generated AC frequency and AC is non-polarized. What that means is that you can test an electrolytic capacitor either-way -either polarity of the black/red lead is fine and doesnt matter to the tester which way you connect it to the polarized cap.

It is important not to test huge capacitors with this tester. Just normal size or small capacitors as found in everyday electronic devices like TV radio computers and other ordinary household type equipment. It is not for big high-powered capacitors.

Capacitors generally have a 2000 hour lifespan. It is a wonder most electronics lasts longer than 90days because that is the warranty period. Capacitor's 2000 hour life is 90days. It is a wonder that devices like tv sets last longer than 90days. I always shut off my equipment and appliances and audio/visual gear & more when not in use. Why waste the life of your equipment - by just letting it run idle?

Runs on 1ea 9V battery. Purchased used in 2011 year. A similar tester is Capanalyzer Model EDS-88A

Some notes on difference between model EDS-88A and EDS-88A series II:

The series II has the words "Series II" written on the PCB. The series II uses 2ea PIC chips. The EDS-88A uses 1ea Pic chip and 2ea large LM chips. These 2ea large LM chips were replaced by 1ea PIC in the Series II. The components and layout are very similar. Identical functioning. I have seen a model EDS-88A with a slot cut in the back with a prop-up style holder (See picture file). My newer style EDS-88A Series II does not have this slot or holder.

I see a big-auction-site listing where EDS was cleaning out their inventory of spare parts on 6/22/15 and feel this partial parts list is very important in case of a need to replace blown components. I have copy/pasted this partial parts list here. The ad showed parts used in the Leekseeker89 and Capanalyzer.

Several photos showing transistors, capacitors, diodes (above pictured) 

Above pictured Duoyi DY294 Transistor & Parameter Tester (Also Checks many other semiconductors and capacitors etc)

DY294 English manual download above (my tester came with a foreign language paper instructions)

This tester has some unique features which allow me to test parts I could not otherwise test. It also internally scales up the voltage for certain tests- for example it can generate over a thousand volts for certain tests yet only 4ea AA batteries power this tester. It tests alot of parts' parameters so it can be compared to book specifications. For example when deciding whether the part is good/bad - comparison of data found in ECG or NTE semicoductor replacement data books - comparing what you see on this tester can be compared with those listed in the ECG or NTE books for their subtitute cross reference part values.

Some tests for varistors or transistors with internal diodes can be checked with this tester. It is a very handy device for alot of things found in most everyday devices- which previously there was no easy way to test them that I know of. Care must be taken to set the dial correctly and not flip the dial after the part is installed otherwise you can expose a part to the wrong test and apply too much power to the part accidently. Keeping a notebook on how to test a part is important so you can repeat that test the same way next time too. The apearance of this tester is deceivingly simple. It is labeled as a transistor tester but it is so much more than that. It not only tests standard transistors but all of the oddball ones too and many more parts.  It is very versatile and performs odd-ball tests that my other testers dont do. There are a few tests that a few of my testers have in common.

On some tests the TEST button is pressed and on other tests the TEST button is not pressed. Read the specifics on whether that test requires the TEST button to be pressed. Note that when the TEST button is pressed - the red LED "HV" next to the TEST button - lights up.

Purchased brand New in 2012 year.

Update 12/14/15

I credit this tester in identifying the voltage on a hard to identify Zener diode. It gave me the voltage and reverse voltage - and was able to match the zener type based in its readings. I know of no other tester which could have provided me with this information. It is a great component parameter tester. Its extreme ability to actually generate high voltages and test components at their high voltage specs (in the case of the above mentioned zener diode 160V) is a very welcome feature. I have other testers whichg identify zeners but thopse testers are only for low voltage parts. This one is very capable. See "Zener Diode Test" on this page to see my procedure notes.

Duoyi DY294 Tester Notes

Test 4ea AA internal batteries condition

(no components connected) turn dial to the right "2a(Ic)" The display shows battery volt (4ea AA batteries at 1.5v each should give you 6volts or better - the tester will work with weak batteries on most functions but some functions require peak batteries to give accurate reading) It is not necessary to press any button with this test.

AC Adapter

6V DC 2A using the jack on lower righthand front panel. + is the center connector. When using the ac adapter - make sure internal batteries are removed.

Voltage Regulator Testing

78XX and 79XX etc insert in 321 holes. With 78XX the regulator faces towards me. With 79XX the regulator faces away from me. Move dial to "78xx" or "79xx" and press TEST button and read display volts. Internal 4ea AA batteries need to be strong for accurate results. For example 7806 installed correctly with good batteries installed will show 06.0V when Test buton is pressed. Make sure your parts legs are free of excess solder or it will "booger up" your test holes as it is a tight fit since the legs just barely fit through the holes.

LED Test

Turn dial to "10mA(Ib) NPN (Put long lead of LED in "C" hole. Put short leg of LED in E hole) The led will shine brighter in other dial positions but this lower power position is safest for the LED as you dont want to burn out the LED - just test it. 10mA is enough to light most average LEDs without harm. Over time/decades of use - some LEDs grow dimmer with age. I suggest that dial is turned without anything inserted. LED should be installed AFTER dial is turned so as to avoid higher power ranges which can damage lower power LEDs. Display shows turn-on voltage of LED. Putting LED backwards does nothing and LCD shows only internal battery voltage of 4ea AAs installed. Typical red LED will show 1.76V for example when inserted correctly. No buttons are pressed during this test.

Zener Diode Test

Use E and C holes. Set dial first before inserting part. Set dial to "200V" NPN. Insert zener diode into E and C. Stripe side = C hole which gives Breakdown voltage when you press TEST button. Insert zener diode with stripe side = E which gives Forward Voltage Drop voltage when you press TEST button. Remove part and move dial to ICEO NPN and then insert diode (both ways) press TEST gives ICEO reverse leakage current. Having good fresh AA batteries installed is important for accurate reading

Varistor "Operating Voltage" Test

If the Varistor's value is 300V or below then use 200V NPN setting.

If the Varistor's value is above 300V then use 1000V NPN setting.

(300V is not a misprint and 200V is not a misprint and 1500V is not a misprint)

Turn dial to "200V NPN" or "1000V NPN" depending on your varistors value (see above note) Locate the capacitance test socket located in the lower right hand corner of the tester. Warning - This is a high voltage test - keep your hands away and dont touch any part of the meter or varistor during test. After dial is set and you have inserted varistor into the capacitor test socket - then press TEST button. The display will show the "operating voltage" on the display. It may vary a little from that written on the part. Release TEST button. Set dial to off before removing varistor. Avoid electric shock by not touching any part of the tester or varistor. This test generates up to 1500volts. Be very careful. I know of no other tester which can test a varistors "Operating Voltage".

Varistors and Disc Shaped capacitors look similar - be sure you identify the part correctly. Only run this test for Varistors.

Polarized Electrolytic Capacitor "Withstand Voltage" Test (medium size or smaller barrel shaped caps)

Locate capacitor holes labeled C+ and C-. Move dial to 200V NPN. Insert the legs of the capacitor into the correct socket hole. The stripe side of the capacitor is the minus side. Read the capacitors voltage and write it down. The way the capacitor is inserted - makes the capacitors value as writton the capacitor itself - faces the wrong way - so writing it down helps you remember - not to exceed the voltage that was written on the cap itself. This is a slow test and takes awhile and is a battery hog - will drain your batteries. Press TEST button and keep it held down until your voltage increases to the voltage written on the cap itself. This meter only tests the "withstand voltage" of the cap. It does not test ESR. It does not test capacitance. I know of no other tester which can test a capacitors "withstand voltage". It will even test capacitors which have a couple of hundred volts "withstand voltage" value.

Remember to discharge the capacitor by shorting the capacitors leads together before and after this test to prevent personal injury from a charged capacitor. Dont touch a charged capacitor's leads or partially charged capacitor. A DC 6V 2A power adapter is recommended for this test (plug into DC6V receptacle located just above the capacitor test socket holes. Otherwise fresh batteries are needed for accurate test (remove batteries when using power adapter plug). Test will quickly drain batteries. A bad cap will not charge or the voltage will cease to climb or will stall or will hesistate. A good capacitor will climb steadily but slowly towards the voltage. Once you reach the voltage - then let go of the TEST button. Do not surpass the voltage written on the capacitor. For example - if the capacitor being tested is a 16V6800uF then do not exceed 16v - after it climbs to 16v on the display - be sure to release the TEST button. I dont know what the consequence of not releasing is - possible capacitor rupture or worse or tester damage or capacitor internal damage - unknown. I suggest only testing it properly.

Transistor PNP and NPN (standard types)

ICEO Reverse Leakage Current test

Turn dial to ICEO (either PNP or NPN depending on which type the transistor data sheet indicates). Use a datasheet or by cross-reference to a substitute candidate data - which legs are EBC or BCE.  Insert into the correct socket holes in the tester as appropriate BCE or EBC. Press TEST button. The display should read "000" to indicate that the transistor is not leaky. Anything other than "000" denotes leakage and the transistor is faulty. Remove transistor. Turn dial to off.

hFE (gain) test (3 tests gives gain at 3 fractional amps settings) - make sure your transistor can handle this amperes

Turn dial to hFE 10mA (PNP side or NPN side depending on datasheet specification) Use a datasheet or by cross-reference to a substitute candidate data - which legs are EBC or BCE.  Insert into the correct socket holes in the tester as appropriate BCE or EBC. There is no need to press TEST button. hFE (gain) is shown on display. Compare to datasheet.

Turn dial to hFE 1mA (PNP side or NPN side depending on datasheet specification) Use a datasheet or by cross-reference to a substitute candidate data - which legs are EBC or BCE.  Insert into the correct socket holes in the tester as appropriate BCE or EBC. There is no need to press TEST button. hFE (gain) is shown on display. Compare to Datasheet.

Turn dial to hFE 10uA (PNP side or NPN side depending on datasheet specification) Use a datasheet or by cross-reference to a substitute candidate data - which legs are EBC or BCE.  Insert into the correct socket holes in the tester as appropriate BCE or EBC. There is no need to press TEST button. hFE (gain) is shown on display. Compare to datasheet.

Example C2166 shows "023" which is a HFE gain of 23 at 10uA in socket BCE.

VCE(sat) Collector to Emitter Saturation Voltage (2 tests at 800ma and 2A - not all transistors can handle this amperes)

Turn dial to 800mA(Ic) (PNP side or NPN side depending on datasheet specification) Use a datasheet or by cross-reference to a substitute candidate data - which legs are EBC or BCE.  Insert into the correct socket holes in the tester as appropriate BCE or EBC. There is no need to press TEST button. VCE(sat) is shown on display. Compare to Datasheet. (be sure your data sheet shows it can handle this 800mA before testing) Batteries must be fresh for accurate results (otherwise remove batteries and use Ac adapter 6VDC 3A)

Turn dial to 2A(Ic) (PNP side or NPN side depending on datasheet specification) Use a datasheet or by cross-reference to a substitute candidate data - which legs are EBC or BCE.  Insert into the correct socket holes in the tester as appropriate BCE or EBC. There is no need to press TEST button. VCE(sat) is shown on display. Compare to Datasheet. (be sure your data sheet shows it can handle this 2A before testing) Batteries must be fresh for accurate results (otherwise remove batteries and use Ac adapter 6VDC 3A)

Diode (standard types) Reverse Breakdown Voltage

Turn dial to ICEO(2000uA) Insert diode into E and C (either PNP or NPN side of dial will work but - or + on display may be opposite) For example on 1N4003 diode turn dial to npn side ICEO(2000uA) stripe of diode goes into C hole. Non-stripe goes into E hole of test socket. Press TEST button. Display shows "000" leakage. Remove diode and reinsert opposite (stripe goes into E hole and non-stripe side goes into C holeof socket) Press TEST button shows "1252" Reverse Breakdown Voltage (weak batteries 5v) Remove diode and turn dial to off.

Dual Fast Recovery Power Rectifier

Turn dial to ICEO(2000uA) NPN side of dial. Insert middle leg into E of large socket. Touch side let to C raised metal contact. Press TEST button. Read display. Release Test button. Rotate Rectifier keeping the middle leg in E hole. Rotal so the other outside leg touches C raised metal contact. Press TEST button. Read display. Remove Dual Fast Recovery Power Rectifier. Turn dial to off.

(Note turning the rectifier such that the middle pin touches C raised metal contact and the outside pin (1 test for each outside pin)  goes into E hole. Press TEST button gives "000" display. Remove Rectifier. Turn dial off.

Example MOSPEC F12C20C gives "000" leakage result and "1257" and "1257" reverse breakdown voltage result (weak batteries 5v)

Transistor Parameter Testing Note

Basic Functional Testing transistors can be accomplished by Gain (HFE_ and Leakage for most  transistors and it will catch most issues. This next section is about advanced transistor testing "parameter" testing.

The parameters of a given transistor can be determined by inserting the BCE legs of the transistor into non-matching BCE combinations of the socket (BEC, CEB, EBC, ECB,  etc many combinations). This produces a wide variety of test results according the the mismatching of leg to socket hole mis-combinations. This "mismatching is not arbitrary and it is not done willly-nilly or random. Follow the below instructions step by step in order to see the transistor "parameters" (I will document this later - to be continued)

HP 990B SMD tester

is a Resistance / Small Voltage / Standard Diode & Zener Diode /small battery / Capacitance (not ESR) tester which has built-in tweezer probes (and included add-on handheld probes). I use this occasionally when I work on surface mount boards with very tiny soldered-in components. The best feature about this tester is its ability to identify Zener diodes voltage rating value (not as accurate as my other tester but good enough to determine if a component is blown). Another unique feature is with the push of a button the tweezer tip polarity changes opposite which makes testing standard diodes simpler as the buttonpress allows testing a diode in both directions easily. 

For example when testing a brand new in the package 4.7v Zener diode this tester will give a value of 4.01V and .063 reverse. Good enough for testing purposes - to determine if a zener is good/blown.

It has the functionality of a VOM multimeter with some additional features ( for example like zener test ) - however it is only for small voltage sensitive rating parts - not for use on big voltages or powerful components. Runs on 2 AAA batteries Purchased Band New in 2012 year approx.

Update 12/15/14

I suggest removing the batteries immediately after use. My first unit  worked just fine for 1 day and one day later was found dead on a few but not all functions - and exchanged by a kind China vendor. I can only suspect the internal batteries caused some issue. I have had nothing but good service from my second unit, and I always take out the batteries. There is no on/off switch.

I use the above pictured IGBT & Mosfet tester when I test the high power IGBTs. It has three leads and alligator clips. The LED lights or doesnt light to show correct or incorrect operation of the IGBT when the red button is pushed. It is a nice easy way to functionally test these parts. Some IGBTs fail catastrophically (melted/burned etc) on devices --to-be repaired- but others fail and there is no outward sign that the part is internally bad. The click sound and the red light means it is a good part. I have run into bad parts - and the tester either stays lit or stays off or doesnt respond to the button press- which means the IGBT under test is bad. It can also functionally test Mosfets. Runs on 1ea 9V battery. Purchased Brand New in 2011 year.

Caseless LC/ESR Component Tester PCB Booster Edition ver 2.2 firmware 1.02K

Purchased from big-auction-site approx end of 2012 for about $20 from China. It is a very common tester with some good features. It doesnt do in-circuit testing or thorough transistor testing. Leakage testing - it doesnt do that either. It does quick component identification including pinous of the lead order BCE EBC ... it does that very well. Even so I just dont find the information that it gives to be useful. When I check a component I compare the book specifcations to the readings of the transistor. I find that measuring leakage of a transistor is very important and this tester doesnt do that. Some newer style big-auction-site testers do measure leakage. But I have been using my BK815 for years and a cheap little tester is no comparison to a profesional arsenal of testers. Even though this less than $20 tester is well worth the money paid. It sits in a small box very little used.

I decided to post my knowledge on backlight for this 1602 LCD display. The tester is a battery hog and NOT HAVING a backlight makes your battery last a whole lot longer. But this simple LED mod which basically costs nothing - every electronics hobbyist has an LED to spare.

The short end of the LED goes on the very end of the single-inline-connector (see pics). The longer LED lead goes on the second to last hole of the single-inline-connector. This demonstrates a 1602 backlight or non-backlight version and which pins (the last 2) are for the backlight. For non-backlight LCD - these 2 pins are missing. A simple backlight is putting a standard LED on the side of the LCD module held in place with a dab of epoxy or silicone caulk. Thats my "CHEAP Backlight Mod" for your Cheap $20 component tester. Otherwise just use a 1602 backlighht edition LCD module and plug it in. It will work just fine but the battery will drain quicker.

This tester uses a standard 9v battery. I normally use a rechargeable battery for everything and these have less than 9V just because it is rechargeable and they produce less voltage than standard batteries do. The tester works with a battery of 6.9volts or higher. 6.9 volts is the bare minimum battery power required.

The side of the LCD module has pairs of empty copper islands - this is where the LEDs go and they face inwards towards the LCD side to light it up. Of course with the 2 missing pins - no power would reach those LEDs - so the user would have to provide those missing pins. The LED lit up shows where the power for the LED or multiple LEDs comes from the last 2 holes on the single-inline-connector. So really this LCD module can handle 4ea LEDs (2ea on both sides of the LCD)

I dont plan on modding my own tester. Like I said the tester is a battery hog and adding LEDs just shortens the battery life even further. Its fine just the way it is. Good enough for occasional use - identifying some oddball transistor or seminconductor that I cant find in any book and knowing the pinout. At least it tells me what the part is and does a quick check - most of the time that is good enough to determine if the part is "probably a good part" 

A unknown three legged part will not be identified or will be identified as a resistor or some other oddball display. In that case I know it is a bad part. Its a darn shame if at that point I couldnt find it in any of my books and I had to rely on the tester to identify it. If it cant identify it or gives an obviously wrong identification (3 legged part only sensing at 2 pins etc) - its probably blown/bad part. Its a very rare thing for this tester not to be able to automatically identify a part - even in a rudimentary way - at least it tells you what the part is - useful for small low power semiconductors.

To a complete novice - the information provided for semiconductors inserted seems "WOW look at all of that infromation" but truly almost none of that information is useful. It doesnt give the specifications of the part which are useful for determining if the part is weak or blown or defective. It often doesnt correlate to the book specifications. It gives the novice the impression that the data is the part specifications- no it isnt. Its not all that useful. But it can be used when no book specifications are available and a quick ridiculous novice check is all you can do to an unknown part. If it is blown - the display will mis-identfy the part as something quite obviously wrong such as a resistor or capacitor - when in fact it is a three legged part- because something inside the component is shorted or crossed or weak or damaged in some way. This tester is good for that sort of thing - as a last resort for figuring out oddball parts/confirming potentially blown parts. (See the picture which shows a transistor 2N 3906 being tested - but it is seeing it as a diode - which it is not. This is a transistor misidentified as something else - so that means it is a blown bad transistor - simulated FAIL by only inserting 2 pins of the transistor)

At this time I do not have a 3d Printer - when I do I will make a case for it. Right now I cant justify the cost of a 3d Printer - maybe I will build one or buy one when prices come down or I find a used one. I have a laser engraver but I feel like cases are better made by a 3d Printer. Laser engravers are great for engraving the decorative front panel. Use the right tool for the job.

Photos show my "LED - Cheap Backlight Mod" for cheap $20 semiconductor component tester.

Photos show 2N 3906 transistor test- FAIL

LED is not inserted this way for testing purpose. LED lights up when LCD lights up. LED shuts off when LCD shuts off.

I own several versions of Willem Eprom / ROM/ Prom/ EEprom / Flash / PIC Programmers ranging from early DIY etched board to the above online-purchased advanced model. Pictured above is a PCB50 which is a digitally selected (no dip switches) pushbutton selected model. I can select the voltage and other paraameters with pushbuttons. The LED bargraph lights up according to my settings. It is exactly like the earlier models of DIY Willem and has the same functionality of my other boards - but I like the digital selection and use it/prefer it 100% over my other Willem programmers. This is a parallel port version which uses the parallel cable to communicate with a PC. I use a dedicated older PC for this Willem programmer. It is powered by the USB cable but the USB only supplies power to it. I have used this WIlem to flash/reflash BIOS and update ROMS and burn chips for use in projects. The Willem programmers are very useful - their only drawback is lack of thorough documentation. So I had to figure out each and every chip setting manually - for all chips I have ever burned. You would think that an online source for these settings would exist - but really and truly there is no source for this list.

I have an interest in compiling this list of settings as I have figured out quite a chip few settings on my own and I keep a detailed notebook on what settings worked for me for each chip model I have burned. I use Willem Pro software version 0.99kb for PCB5.5c running an older pc dedicated for chip burning which runs WinME and has both a USB and parallel port and 1GHZ processor which is sufficiently fast enough for high quality burns.

I have successfully figured out the settings for the following chips using Willem, and I have made notes for the following:

PIC12F629

SST 49LF040B

SST 49LF004B

SST 49LF002A

Winbond W39080APZ

Winbond W39V040BPZ

A29002IT-70

SST MPF 39SF020A

Winbond W49V002AP

My Test Notes on ODD parts

Blue non-directional Diode TIP DB3 is used along with TRIAC When testing a blown DB3 showed as 26pf to 28pf on caseless component tester. And when I bought a replacement exact match - the brand new one showed as "no component or unknown component." very easy to mistake a good part as being "open/blown" In this case I changed it out with the new one.

Vacuum Tube Testablility For U-Test-M Tube Tester

I am making a list of testable tubes here. This list is not necessarily about cross referencing. This list is about what settings to use for the U-Test-M Tube tester - as there are more tubes in existence than are listed on its rolling chart. So this Testability tube list will allow me to take unlisted tubes and know which "known tube" it is tested the same as on the U-Test-M roll chart.

I hope I explained that clear enough - this is not a substitution chart for you to swap tubes in your TV set or Radio. This is a chart which expands the capabilities of the U-Test-M tester. I need to look up your tube on my list and then find an underlined tube heading - then use that "subtitute tube number" to look up the setting in the roll chart. It is an in-direct method of expanding by many times the capabilties of the U-Test-M.

The U-Test-M is regarded as the pickiest of all of the testers- people regular folks who repair their own TVs and Repairmen often say - "when I test that tube on my Hickock it passes just fine - but on the U-test-M - it fails it. That XXXX drugstore/tv repair shop just want to cash in on selling tubes. Dang-nabbit (or worse)" Well I look at it this way - The U-Test-M is for people who want to restore a tv or radio to top notch condition - rather than "good enough". Still it doesnt test Mutual Conductace - so really having more than one tube tester is a good idea. I plan on owning a HIckock and a U-Test-M - Both (I dont own any tube tester at this time). There isnt any reason why a shop should only have one tester. If the tube passes all the tests from every tester - then that tube is very good. If the tube is very good - it should be able to pass even the U-Test-M. I'm still looking for a U-Test-M model 2500 I havent purchased one yet- they are usually sold by sellers several states away and I'm hoping to find one that is within driving distance. Let me know if you have one for sale.

With tube based electronics - the weakest point is not the tube - it is the paper and wax capacitors - that is the souce of most problems. The tube is easy enough to se if the filament is glowing or not. Just becaus the filament is glowing - doesnt mean the tube is good. With the invention of the ESR meter - testing those old caps/replacing a few bad ones is a breaze and usually enough to get an old set up and running. But the U-Test-M made testing tubes easy enough for the Do-It-Yourselfer and I remember a local Zayre store (you dont hear that store name too often anymore) had a U-Test-M model 2500 at the front of the department store just in front of the cash registors and to the right of the Service desk. I can remember testing tubes at the Zayre store (as a customer using the stores self-serve vacuum tube testing machine in the middle 1970s approx) The Zayre store was a department store like Kmart, Target, Walmart, Venture etc.

It will take quite a while to make this list and may contain errors so use this on an at-your-own-risk basis - as I will do my best. I am using a multi-column feature and this is something that is new for me when building my webpage - under construction - your patience is appreciated. This section Commenced 1/25/14

Alunar HB-R100 3D Printer

I purchased this used from big-auction-site in very good physical condition with original box September 2016.100mm x 100mm x 100mm build volume. Standard Non-heated bed for PLA only.  1.75mm filament. I see that the mainboard is Chitu - so I decided to upgrade it to heated bed and ABS capable. I like the 2.8" color touchscreen display and the sturdy thick steel construction. The standard use of a common reprap nozzle/heated tip system, spool feed system, ALL 5ea standard identical Nema 17 stepping motors makes repair and upgrades possible with common reprap components.

The purchase of this 3-D printer is driven by my need to make cases/parts for several testers- which the vendors sell without a case.

I ordered a WIFI module and Heated Bed module as Add-ons for Chitu mainboard. I ordered a standard 360watt 12V power supply typical for DIY 3d printers (I spent a whole day fixing this $20 brand new aftermarket power supply- unsoldered torroid transformer, straightened bent heatsink, retap threaded holes, bent aluminum case, etc). The standard power supply which came with the Alunar HB-R100 is not powerful enough to drive a heated bed- hence the need for the add-on module and add-on power supply.

***********The following paragraph has INCORRECT conclusion about cause/solution***********************

Geiger Counter "Bella DBG-01N"  БЕЛЛА ДБГБ-01И

Made in Ukraine or Russia. My unit is brown plastic and some similar models were available in white, red or other colors and stickers. Some units are marked DBG-01i (mine is not marked with an i) Since I dont know Ukraine language - it looks to me like this model should be called Benna or Bevva or gEVVA or bEVVA or who knows what the correct transaltion is. But when I look online - I see that most people refer to this model as "Bella Geiger Counter" and by searching under this - you will find many videos on youtube and online websites selling parts and units.

I purchased mine in early 2015 in non-working condition from big-auction-site. I plan on restoring its functionality and will post my repair here. I estimate the date of mfg is approx 1983-1989. This was a very popular unit and many people used this model during Chernobyl accident to monitor levels. It is one of the industry standard models for obtaining readings and uses 1 internal sensor SBM-20 tube which is sensitive to Gamma rays and X-rays. It uses one standard 9v rectangle battery.

Also see my other webpage

http://www.drviragopete.com/scanning-electron-microscope.php

The other webpage of mine - has to do with restoring a scanning electron microscope. I am concerned about getting irradiated / x rays /gamma rays from this equipment if improperly adjusted. So I decided to buy a geiger counter so I can avoid that harm. SEM microscopes are not considered unsafe as they tipically produce xrays internally but are well shielded. However that is refering to a properly working SEM. Mine is a fixer-upper and I need this geiger counter to make sure I set it correctly and maintain it.

Another good use for a geiger counter with X-ray abilties is testing of vacuum tubes - specifically picture tubes on TV sets. For example obtaining a slightly better brightness on an old picture tube - may make me crank-up slighly on the flyback transformer but only slighlty. See if the flyback is tweaked too high - the filament inside the "picture tube" yoke/neck at a certain poiuntg will produce unwanted xray or other radiation.

Radiation is not a toy and I see too many people using their geiger counter to play with radioactive rocks or other objects while listening to the Geiger counter "going nuts" ticking and beeping its warning while the user handling the samples. I suggest that people who use their geiger counter - should use it to save themeselves from harm -rather than as a toy. Specifically - if the geiger counter shows an unsafe level - take immediate action to avoid exposure or correct it so that the source is put-away/solved safely. Thats my advise.

A reading takes about 1 minute.

My General Operating Instructions Notes

1. Top button is reset (LED will flash as an aknowledgement when momentary button pressed)

2. Rightside Buttons (slide up down switch to select)

    A. Upper is Audio Click ON/OFF

    B. Lower is Power ON/OFF

3. Place unit at or near source. Press reset to begin new counts. After approx 40seconds the display translate the number of counts into a whole number with decimal point and additional disgits. This number is your micro sieverts per hour. This meter has an accuracy of within 30 percent plus or minus. Gamma and Xray sensitivity only. Use only as a guide and use your own best judgement on what is safe or not. Its not going to pick up every ray or even close to all of the rays that may be or may may not be present.

I can tell that this will be a difficult circuit to diagnose because the IC chips are not in English and the electronic components are different looking apearance-wise and marked in a differnet language. I will need to figure out English equipvalents and use my best judgement and equipment to figure out what is the problem with this non-working unit.

I see normal background safe/normal radiation counts is somewhere between 10 to 25 clicks as typically displayed on this model. It has a 4 digit LCD display which looks like this 8.8.8.8 Often on this model's LCD display there is some black bleeding internally as the liquid crystal seeps or glass separates or cracks etc. I see no bleeding on my own LCD which makes me think it was never exposed to extreme cold. LCD screens are damaged or destroyed by extreme temperatures both hot and cold. I felt that this unit on big-auction-site was worthy of putting time and effort into fixing as it is physically in good shape and complete - right down to the battery cover.

Update 1/15/15

I received my geiger counter and got it to work and un-modded it as much as possible. I have posted a more detailed description of what was done on my "scanning electron microscope" page. It didnt need any electronic component repair or replace. It was just a matter of un-bodging it bringing as close to original as possible.

Update 6/2/16
Unfortunately my Bella Geiger Counter is not working. I wanted to use it to test a CRT inside my film equipment which scans using a flying spot scanner - when I went to my cabinet to get my geiger counter - it was in a ziplock bag and no 9V battery installed. I put a fresh brand new battery in it and I see all zeros O.O.C.O and one of the zeros is incomplete "C" due to one of the LED segments unlit. I see no incrementing or tic tic tic. It is unresponsive. I pressed the zeroing button on top of the unit and red LED lit but I see no sensing of background radiation at all. So unfortunately I was unable to test my CRT inside my film scanner (one of several extra parts units which I am trying to rebuild/restore/combine into another good one) which I am currently repairing. I dont know how it could be non-working as it has been undisturbed in the cabinet and safely stored. I enjoyed using it and I hope to find time someday to fix it. I used it about 12 times in the last year and was a very useful tester. I didnt do anything to cause it to die - was just stored in a cabinet.

Update 6/7/16

I decided to open it up and see what is wrong. I tried 2 batteries and still was stuck at O.O.C.O and I disconnected battery and tried moving the bodge wires and then reconnect battery. No change. Disconnected battery and then tried moving all of the components over just slightly - that was it a loose connection on one of the components. I reassembled after it worked. I didnt touch up any solder joints. There is a certain point of - "if it aint broke - dont fix it" Im glad that it works again- one segment of the display shows a C rather than an O but nonetheless - it is useful again. Normal background radiation differ from minute to minute but is somewhere around 7 to 13 clicks. If I put it on a stack of extra floor tiles I get a couple more clicks around 13 to 15 - so I can cell it is working normally and LCD numbers are incrementing now. The mfg coated the PCB and components with a clear coating (varnish? Clear paint?) and I dont wish to disturb that - so it works and Ill not reheat all of the solder connections.

VZ IC Tester pictured above (list of chips shown at bottom of page on left side in blue) My IC Tester # 3

It has search function and chip number can be manually typed using the keyboard. This tester was sold under 2 different brand names. The components on the internal circuitboard are sanded to hide part numbers- which makes repair very difficult as only good working chips are identifiable. The case is not precision molded - it is a heavy plastic which is slightly imprecise - the battery lid does not open/close easily due to this imprecision. Much care in handling the battery cover is needed. The vendor sent me a replacement battery cover at no charge. The vendor was helpful. This is a very nice tester and at the time I purchased it - it was the lowest cost handheld tester available. It does a good job identifying / searching for unmarked chips. I bought mine through big-auction-site. Later this same mode was sold through a commercial online big retailer for more than twice the price I paid for it.

Manufactured and purchased new in 2012 year.

Update 12/15/14

I caution the users of this tester and rebranded/original model which bears a different name. This tester has a very small tolerance for deviance in supplied power. It will blow out if any ordinary power adapter is attempted connected. I suggest ONLY running this IC tester on 9v battery. Internally some chips have been sanded down removing the identifucation of the chips. This renders the tester difficult to fix by end user as identifying a non-working sanded-down chip is not possible. Heed my advice and only use batteries. The instruction manual gives the wrong voltage for the dc power port- dont attempt to connect 9v with a wall type adapter to the external power jack. Heed my advice and only use internal battery.

GUT IC Tester pictured above (list of chips shown at bottom of page on left side in white) My IC Tester # 1

It has search function and chip tested can be manually selected from internal Menu lists. This tester was sold under various names by several vendors. The diagram on the front of the unit is handy - it tells you which chips to install up orientation or down orientation. The down orientation chips need to be at the bottom of the socket. The up orientation chips need to be at the top of the socket. There is a clearly marked OFF procedure. (on another brand this off procedure is not clearly marked - see my LIC tester further down on this page)

I bought this used and had a heat damaged LCD display. I ordered a new LCD module which is a standard type. This tester now performs very well and has no cosmetic or functional issues. If I didnt tell you - no-one would know it had been repaired. The only difference is the LCD contrast is higher on the new lcd module than on the original (original LCD was dim) and display has a slightly greenish color.

The aftermarket LCD module was purchased on big-auction-site " HD44780 16 Character x 1 row LCD display w/light " and the original one was not backlit and was damaged as received from seller - bleeding LCD symptom towards the center. A perfect replacement non-backlit (jujst like original) screen choice is 1602 16character x 1 line - instead I chose the backlit version and had to modify the internals slightly to make it fit as it is thicker. I have not hooked up the backlight. It runs fine without the backlight. At this time I have not figured out where to connect the backlight pins - the screen works beautiful but no backlight at this time.

Manufactured approx 2005 year estimated. Purchased used in 2012.

Precision-Motion Chiptester Model CT2 pictured above (list of chips shown at bottom of page on right side in red) My IC Tester #4

Notes: This is the full version machine with optional internal ROM upgrade factory pre-installed (" CT1 with 4164 & 41256 TEST "). Originally sold by Digi-Key Part Number CT2-ND in approx 1988 year. There is no keypad to enter the chip number. Simply insert the chip into the socket. The manual tells you the correct display for a good chip. Usually the display shows the last few numbers of a chip - as the correct response for a passed test. On other chips the display may show a letter and number combination or simply a number or a subtraction symbol next to a number etc - the manual deciphers the display and what it means. Reading the patent also helped me understand what this tester does. It is very sophisticated yet simple for most chips. There are some chips in the list which require 20 adapters to be self-made as some pins on the self-made adapter need to be cut-off or jumpered. I do not have any of these self-made adapters. Between all of my testers - the chips which the Chiptester requires a special adapter to be self-made - are available as part of a built-in test on another one of my machines. It is important to look up the chip number in the manual before plugging it into this tester. Estimated manufactured 1988 approx year.

This IC tester was purchased used in 2012.

YBD IC Chip Tester pictured above (list of chips shown at bottom of page on right side in yellow) My IC Tester # 2

Purchased and manufactured New in late 2012 year online from a Hong Kong Seller. Purchased the optional add-on 3-socket adapter 2013 year direct from the mfg. No automatic search function on this tester. It has loop function. The number of ICs this unit can test is very very extensive. For some ICs - the chip must be put with pin one at top of ZIF socket - other tests require the chip to be put in with pin 1 of chip to pin 2 of the tester socket (the display prompts the user how to insert after the chip number is entered.) The manual's diagram showing how to use the adapter differs from the markings on the 3-socket adapter - so I have not plugged this $40 3-socket adapter in at all. The mfg is checking on this to see if they can provide me with an updated instruction sheet to clarify the proper use of this adapter board.

Update 2/25/15

The mfg never did provide the missing information (but I did get responses to email). I paid quite a bit of money for the adapter board plus Western Union fees and it added up to be alot of money. But I'm glad to have this board. I have communicated with several buyers of this same IC tester and one of them also wanted to buy this add-on board but was told it was not available. My understanding is that the person who created this add-on board (mfg former employee) is no longer there and the current employees do not know the answer. Also the board was not available for purchase - another owner was told they dont have any more.

So that makes me the only person who actually has this board - possibly?

I studied this board thoroughly and have created an instruction page on chip orientation and orientation to plug into the IC tester. I didnt want to run the risk of just randomly trying things - so I carefully studied the board and determined how each pin on the board leads to each pin on the DIP male plug on the end of the ribbon cable.

The basic purpose of this board 

When you type in the chip to be tested from the chiplist - you enter a sequence of numbers corresponding to that chip. For example when you want to test chip 8255 you key in that sequence on the keypad. Usually chips can be tested directly on the console. But for certain chips on the chiplist the display shows OU-1. This display tells you that the testing of this chip requires the "Special Device Testing Board YBD-5" (see my photos of this board). The manual that came with my tester is mostly understandable but leaves you scratching your head on certain topics. Especially regarding the add-on board. So I wrote my own manual for the YBD-5 board. I also put homemade stickers on it; So, I know the orientation of the ribbon cable and orientation to insert the chips into the sockets.

Here are some photos of the board, my own instruction page, and other misc photos showing my actual unit in its protective packing material. It is a very nice IC tester - I spent alot of money on the tester, shipping, bank fees, western union fees, add-on board, etc. Was it worth it - yes I'm glad to have it. I can test chips that are unique to this tester- also it is a good second opinion and pulls its own weight in determining faults.

I had to figure out the answer to my own questions. I was basically on my own regarding this board. I feel that I understand it now and took alot of effort on my part.

What is not clear in the MFG's manual

1. Orientation of ribbon cable and red stripe side

2. Orientation of chips on the sockets

My photos show the correct orientation. The instruction manual explains how to use the add-on board, orientation, schematics/board layout and traces, etc. It is not often I use the chips that the add-on board handles - but I can now refer to my own manual to refresh my memory. I never have to fumble around with this anymore. Now I can use it. I printed the manual on my color laser printer Samsung CLP-300 which I purchased a few years back at OfficeMax on closeout/demo unit. It prints beautiful glossy perfect pages. I use that printer very sparingly only for important things. What I'm trying to say is this is a beautiful instruction manual - I put my best effort into it.

They didnt make 3 separate adapters - but instead combined it into one board. Either way works- but schematically it would be much simpler if it was 3 adapters. The display tells you which of the three adapters to use. But since there is ONE adapter board - you plug the chip into the corresponding section of the board. All this adapter board does is cross and switch around a couple of pins. Its just wiring traces. There are no electronic components on the add-on board.

Dont jumper on this tester (some other testers have you insert jumpers between pins or add capacitors to certain pins) - BUT I WARN YOU - jumpering is not applicable to this tester. Certain pins must be raised and then that pin is crossed to where another raised pin is - basically switching pins around. Thats basically what this adapter does. If you simply jumper - you'll short something out inside this tester- dont do that.

One funny thing about this tester is the word "PLEASE" is displayed when it is ready to test. A better choice of word is "READY" It makes a beep boop type sounds which remind me of a Milton Bradley SImon game from the 1980s.
I like this tester - it tests alot of chips including some older computer motherboard type support chips.

MCT IC Tester pictured above (list of chips shown at bottom of page on left side in green) My IC Tester # 5

Made in 1989 year approx. Memory chips DRAM are installed in the test socket reversed/backwards and furthest away from LCD. Has auto search function and also arrow keys to select chip from internal list. I have the version with the yellow button (some other units have a red button) Purchased used in 2013 from USA seller. This is a very speedy tester and with a press of a button recognizes a chip and tests it very speedily. You can also manuall\y select the chip number from a chiplist and scroll through that list. It runs on a 9v standard battery. Memory chips are tested upside down (notch facing user) and TTL chips tested up-side-up (with notch facing away from user)

I had 2 identical units and gave one to a family member (both purchased from same seller) Both units had a dim LCD display. Dim LCD  is normal for this model. Use it under a good light source such as a lamp.

TSH IC Tester pictured above (list of chips shown at bottom of page on left side in orange) My IC Tester # 6

Here is a text file in Word format - you can use an online viewer if you dont have the soft ware "Word" But this is just your average instructions in which it says the P key is for backlight. Another ridiculous online instruction in which it gives false information - can anyone reading this translate the image which contains foreign language text - that may contain better information?

Micro Scences MSI Digital IC Micro Circuit Tester Model ICT-101 (pictured above)

IC Tester #7.

(List of chips left side purple color - see below)

There is an empty socket on the front of the machine - which  is for 24-pin IC chip clip (was optional accessory - but mine doesnt have this clip. As I read from the book this optional clip is only for 74154 IC which is a narrow .300" IC same as most 7400 chips so a special .300" IC clip 24-pin is needed and these clips are uaully designated "24/3" to denote 24pin clip for a standard .300" narrow IC). I have 2ea total IC testers that can test 7400 TTL and 4000 CMOS chips in-circuit while the circuit is powered on (the MSI ICT-101 and the B&K 560). It is a large tester 5"x12.5"x11.63" and weighs 7.63lbs. This tester is estimated to be mfg in 1983 and is complete with manual and ground cable (Pomona Electronics 3780-36-0) and 20-pin ribbon cable with end clip. Most of the internal chips are 7400 series with 1 static RAM and several ROMs. There is a D800 microprocessor in there also. A board which looks like a memory module is covered in factory black epoxy resin to shield the part numbers and protect from anti-static. The 2ea upgrade ROM which adds a few more ic chips to the list - is not in my machine (I have the standard ROMs with 2ea additional empty sockets for the upgraded ROMs to go there. My sockets U10 and U13 are in need of the upgrade ROMs. If you can provide these missing U10 and U13 ROMs - let me know. I realize it will be difficult to find these ROMs 35+ years later.

Here is my photos and description of how I fixed my ICT-101 Tester. It is a free download and copyrighted All Rights Reserved. Do not post it in forums or share in any way. Instead - refer people to this page or give my contact info so they can download it from my webpage directly.

Update 5/29/15

I have acquired a second fixer upper ICT-101 (purchased Oct 2014) which has the 204 Rom Extended Chiplist stored on 5ea 2732 EPROMs. I am still looking for a 205 chiplist which is enhanced even further. As I work on repairing this second unit - then I can take advantage of additional testable chips- above and beyond the standard chiplist.

This IC Tester has internal diagnostic checks and functionally tests itself in many ways when powered on. The menu lets you choose settings for ROM RAM CMOS TTL and more. My tester does not have the optional RAM/ROM test feature. My tester is a basic model and only for in-circuit testing of 7400 and 4000 series chips (this tester does not test every chip in these series/families of chips). The add-ons were not purchased by the prevous owner and this is a factory stock machine - now fully functional - after I replaced about $25 worth of discreet (common solder in place type) components and 2ea ICs purchased online. When I purchased it - it had a scrambled/garbled display (looked like this @#$%&*@# with all random characters) and was unresponsive to key presses. It had a bad transistor in the display board and a bad SCR and 2 bad 7400 series chips. The 1ea desoldered/now socketed static ram chip 6116 tested fine on my tabletop IC tester. Luckily the proprietary memory board was fine as the factory covered it with black epoxy and would have been difficult to remove epoxy. Since all of the chips were soldered in place - I had to make my own IC desoldering tool by hand and I removed each chip and socketed it. I checked each componenet one-by-one with a parts tester BK Precision BK815 & various handheld & tabletop IC testers shown on this page. The zener diodes I tested with Duoyi DY294 tester & TSH-021 IC tester which gave correct voltage checks (see above photo which shows germanium diode inserted into IC tester for voltage check)  Several parts were replaced with NTE brand replacement parts purchased from Radio Shack online and a couple of parts were purchased online internationally. I desoldered chips carefully and used the same chip to go back into the IC socket. I did not destroy any chip when I desoldered with my homemade desoldering tool and was able to test them on my IC tester and knew they were fine. The online auction I purchased this ICT-101 IC tester from says it was "military surplus". the preevious owner attempted to fix it and boogered up alot of things. It took alot of un-boogering to correct. I solder very well and my solder joints look pefect.

The general concept for using this tester is - you have to have a live powered-on board to be tested. But the board under test cannot be underway. What I mean by that - is the electronics have to be idle and not operating. Powered on but not operating. The microprocessor should be removed or the crystal disabled so there are no oscillations. The ground is connected from the powered on board to the ICT-101 tester. Very important - the ICT-101 needs to be powered on first before any connections are made. It tests CMOS and TTL Digital Logic ICs in circuit on live boards which are not underway. I hope I explained sufficiently - what I mean by "powered on but not underway" as I'm trying to phrase things in everyday terms. The book calls it "the board has to be in a static condition" and "devoid of active ICs" and "effectively removing disabling or tieing clock generators."

The tester should never be exposed to 6v or more (6v would kill the ICT-101 tester). Check voltage (This is a 5v tester only) before testing and removal of oscillations prior to use. The tester should not be clipped onto a chip more than 1 minute or it may weaken or ruin that chip. A sense of urgency in quickly testing a chip is necessary. You cant stop and answer a phone or shuffle papers while using this tester - otherwise you will burn out the chip under test - or damage the tester itself. Any possible future repair should be easy now that all the ICs are socketed. Test equiment should always have socketed ICs - that is my opinion - as it makes for easier repairs and fault-finding/troubleshooting. It is interesting that the mfg of this ICT-101 tester had a lifetime warranty on this tester and is no longer in business. The book states that an ICT-101 is necessary to troubleshoot an ICT-101. So it takes a tester to fix a tester. If I had another in-circuit tester - I could have removed the microprocessor, clipped on the test clip, and checked each IC one-by-one. That would have caught all of tha bad parts except the SCR- which would still have needed to be manually desoldered for testing out-of-circuit. I have alotof IC testers as a "second opinion" about a parts condition is helpful and avoids false pass/fail and replacing good parts un-necessarily. This in-circuit tester is one more "second opinion" about an ICs condition.

This IC tester was purchased used from a USA seller in late 2013.

Update 8/5/14 I have completed the machine by addiing a second ribbon cable in the righthand socket. I found a professional 24-pin IC clip and ribbon cable made by Logic Connection which is NOS New Old Stock purchased from big-auction-site. This clip was hard to acquire as it got lost in shipping for 3 weeks and ended up in another country. The honest person who received it - sent it back to the seller, and then I received it after about 3 weeks. I also added a 24-pin ribbon cable connector. This now gives me the ability to test just one 24-pin IC chip on the chiplist which is a wide style chip.

 Update 10/15/14 I have purchased a 2nd identical unit from an international seller. This unit was the sellers 2nd unit and didnt work- it had a scrambled display for example &%&%$@# is what it looked like. The seller then disassembled it and never attempted a repair and it sat in his shop for 10years disassembled. He sent me photos showing all of the major parts like boards and case and front and back panels. I have included those photos here which shows the as-is condition. I will chronicle the repair of this unit here. I suspect it has the same or similar bad components as my other ICT-101 tester repaired with the very same symptoms/issues. I suspect this model must be turne on and off very carefully with no bounce in the power switch otherwise the same discrete components and ICs fry - see my above article on which parts were replaced on my other ICT-101. I will need to wait a month approx for this non-working disassembled tester to arrive.

Upate 11/4/14 I have received this second ICT-101 and arrived from Brazil seller. The box was shipped very carefully and nothing heavy was placed on top. All of the parts arrived as sent with no shipping damage. All boards have corrosion and I knew the condition as the seller sent photos. It will take alot of work to restore. I am glad that all boards and small pieces were sent including all screws in a plastic bag. I look forward to having a working second tester of this model.

Update 6/15/15

I tested a brand new NTE5552 which I bought to replace a 2N6395 SCR and I found that the new part gives the same strange Lissajous pattern vertical line. Also my SCR tester gives the same LED lit then when the button is pressed the LED goes out for as long as the button is pressed on the tester. This LED response on the tester is opposite of normal. I made an error in thinking that the original part is blown - when in fact the 2N6395 wasnt blown. SO I ordered a $6 replecement part for no reason. It happens to the best of us- I try to keep the misordered parts to a minimum. I put the new part back in its package and will save it in my inventory. So I would consider the power supply fixed at this point. I thought 2 parts were bad but in fact only one was bad/weak which was a 2N3055 which I had in my inventory which replaced a .08 leakage part with a 00 leakage part. Power supply repair is now done. I need to rewire the transformer from international voltage to 125V AC US standard.

I usually make a detailed notes sheet when I am fixing something. I put the pinouts, measured values, notes etc. I will include the scanned notes pages here which shows my diagnostics on all the components on the ICT-101 power supply.

This is a Portable Linear IC Tester LIC and is a handheld tester. It is my only linear IC tester at this time and my 8th IC tester. It has the same shape and style case as another one of my testers. I'm glad to have purchased this tester as I was looking for a used one for a long time. This unit came with the original AC power adapter which is 9VDC 500ma or can run on 2ea standard 9Volt batteries. Several companies sell this tester under various name brands. I have listed the chips it can test at the bottom of this page on the right-hand side in grey color. This tester was purchased from a Canada Seller on 11/13 and shipped to USA. Purchased (New Old Stock NOS and never used by previous owner) in 2013. Manufacture date estimated 2010 (this is a currently available item as I am writing in 2013).

The label is clearly marked for chip and semiconductor orientation of inserting in the socket. The Power Off procedure is not clearly marked on the unit. Here is how to turn off unit (Hold Down "Type" button while pressing "Down Arrow" Button) I know this only because I have a "sister" unit very simiar (see GUT tester on this page above) which has it clearly marked on the label.

This tester has helped me numerous times in testing voltage regulators such as 7805 etc and ICs which are analog such as the LM series and many others. The chiplist is very strange in that you have to scroll through all of them and just in random order. They didnt even put similar semiconductors next to each other in the internal chiplist. There is alot of scrolling and hunting until you find that in the very long chiplist - but once you find it by scrolling through the chiplist - it does test the component very well. I am very careful about making sure the proper chiplist component is selected - for the correct semiconductor component to be tested. I am VERY GLAD to have it. It has saved me alot of un-necessary replacing of suspect parts.

This Tester was purchased brand new NOS from a Canada Seller in 12/2013. This is my IC Tester #8

Notes:

Update 9/07/18:

I attempted to use my Artsign JSM-40 40Watt CO2 laser engraver today (bought used from a local High school 10 years ago) to make some cuts but the machine didnt startup properly and no homing or movement from the motors. I looked inside for obvious things first like burned fuse or burned/swollen components. I noticed that 1 red LED on power supply was lit and the other one was not lit. I disconnected the power supply conector and measured voltages and found one pin without 5V. I removed the PCB and checked all capacitors and found perfection there- like brand new caps. I checked diodes and found all were good. I removed the L7805CV and tested on linear tester and see a value of 4.48V and should be 5V. I desoldered an identical voltage regulator from a known bad electronics board in my junkpile/inventory- and found a questionable L7805CV - so Im not sure which one is good bad as one reads 4.92V and when put in reverse shows 4.42V and the other one shows 4.48V one way and OV the other way. Makes no sense- so I ordered a lot of 15ea L7805CV from international for $1.50 and will wait for it to arrive. Either way one of the old regulators are bad - one or both. Hopefuly that will fix my CO2 laser engraver as it apears that the 5V was low enough where the opto device wouldnt turn on that pin to power the controller. That is my hunch and the clue was the non-lit LED. It is good to have this tester and has helped me discover quite a few bad components. When I see something flakey - like giving me a reading when I put in backwards or shows less voltage than should be- those are good signs that it is bad/weak/etc and is worthy of buying a part to be sure. I have quite a collection of scavenged parts but in this case I didnt have any already removed parts to choose from. I didnt want to put a potentially flakey voltage regulator into my laser engraver. I could have sworn I had a bunch of 5V voltage regulators but I must have used them up over the years fixing electronics for myself or for others.

Update 9/21/18

I received 10ea L7805CV in a flat antistatic tube and was a real bargain for 75cents including shipping. I fixed the laser engraver and also a project which I never could get to work (a DIY eprom programmer) and now I see why. The bad voltage regulator I borrowed from it was also bad.

This linear IC tester reads the following for a brand new L7805CV 4.98V in both directions/backwards and forwards. My bad #1 showed 0V in one direction. The bad #2 displayed 4.98V in one direction and 4.4V in the reverse direction. This linear tester has helped me repair quite a few items.

I have saved these two bad parts because they are easy to confuse as being good. Using a magic marker I wrote "BAD" on it which means a defective part. I keep confusing ICs and parts - as they are good for testing testers.

The reason my CO2 Laser Engraver 40watt didnt work is that the voltage regulator was weakened to the point where it was below the threshhold as the bad part showed 4.4V and the opto-device which it powers must have required a slightly higher voltage to turn on. This may explain why last year the laser was flickering while running on one long job I ran. It is possible that the flickering was this borderline pass/fail part which just recently crossed that line. The school that sold me this unit about 10years ago probably used it alot. I just use it occasionally. Im glad it works as I have to make some parts for a customer order.

Above pictured is a B&K Precision model 560 (sometimes referred to as a BK560) Digital IC Tester. It has a 24-pin ZIF socket for inserting chips for out-of-circuit testing. It has an IDC header for connecting an external clip of various pinouts. This is my second tester which can perform out-of-circuit testing. Soldered in chips can be tested without desoldering in most cases. There are times when the chip must be de-soldered from the board before testing. Since I purchased this machine used -it came with no ribbon cable clips so I made my own set of 5ea clips 14-pin, 16-pin, 20pin, 24-pin and a 20-pin microclip for SMD chips (I see quite a few 7400 series chips which are SMD nowadays so this miniature clip is necessary to test the SMD mini IC chips of the various chip families) This tester also has the ability to learn an unknown digital chip's truth table and store that data into memory chip storage for future comparison (see 4ea empty IC ZIF sockets one of which has a data storage chip installed). The list of chips is very long and I will add this chip list in the future at the bottom of this page in turqouise color and right-hand side as my time permits. This is my 9th IC Tester. I will add a photo of my self-made clips at a later date. For in-circuit testing using the external ribbn cable clip- the circuit must be powered-on but not in-progress. By not-in-progress I mean that the circuit must not be running or operating - but it must be receiving power. To further clarify - The crystal oscillating the circuit must be disabled so that the circuit is not underway or in-progress. The crystal oscilator must be removed. For eaxample when I test diskette drives - I connect the 5-1/4" disk drive to a PC power supply but the drive itself is not connected to the controller card. This in essence removes the crystal oscillations and satisfies the requirement that the circuit under test is not in-progress. The tester tests chips which are at a standstill and are not processing any data etc. This is my second in-circuit tester and the same not-in-progress requirement is found in my other tester for in-circuit testing.

Wanted:

I am looking for the decorative plastic cover which fits over the Eprom sockets. Either a black one or white one would work. Mine is missing this cover - the factory image shows with the cover and my own photo shows without cover (purchased w/o cover)

I am searching for the rare software option for this tester. The software named "AK560" or possibly a different name - will allow a vintage PC to connect to the back of the 560 IC Tester through the RS232 serial port. The software allows creation of customized IC test program - for chips not in its internal chiplist. I wonder if anyone reading this has a floppy disk (5.25" ? 3-1/2" or CD-ROM) with this vintage software which I am seeking?

This tester was purchased from a USA Seller on 12/13. This is my IC Tester #9

Update 6/22/15

I ordered 1ea 12" x 12" x 3/32" (.093") sheet of black ABS Textured and 1ea sheet 12" x 12" x 1/16" (.060") These sheets were purchased from big-auction-site and cost was approx $15 for both including shipping. Using my laser engraver, I will do my best to make a replacement cover for this IC tester - then glue those pieces together with Weld-On #3 which is a plastic solvent and fuses the material together. I was not able to find an original replacement after years of searching. I will fabricate my own. I plan on using these sheets for several projects including making a back panel for my semiconductor analyzer/battery pack (see PST-5000 further up on this page). If I cut carefully - this material should be/may be enough for both projects. Another alternative is a 3d Printed part - I do not own one at this time (I will buy one sometime in the future when prices come down). The ABS textured sheet cut/fabricate/glue will give a more accurate glossy testured finish which more closely resembles the original.

Update 11/18/15

I drew the following 4ea illustrations (using Microsoft Paint) of making your own Test Clip Ribbon Cable for use with B&K Precision model 560 IC tester. These diagrams show the 1:1 correlation between the IDC male connector and the IC under test. For example the top 2 pins of the IDC connector correspond to the top 2 pins on the IC being tested. 

Whether you choose to make a professional cable using real parts like IDC 26-pin female or ust makeshift jerry-rigged amateur wiring is up to you. I suggest making a good-looking cable that is professional looking. I purchased my IDC connector, and misc items, and my IC clips on big-auction-site.

Update 9/3/16

I purchased an original BK 560 manual from big-auction-site and posted a photo of this blue cover manual here. 

Here are a few photos/drawings.

The above pictured Berkeley 998  is a Linear IC tester and is a vintage analog piece of equipment (estimated 1965 to 1975 estimated mfg year). I purchased the manual and tester from different sellers. I feel fortunate to own it as it is rare. I plan on testing op amps and voltage comparators. To be honest the manual only gives one example on how to use it and I need help on understanding how to use this tester. All of my other testers are simple to use and operate. This vintage linear IC tester is very capable machine but I need to learn and am going through the book but I can see that the book's one example is insufficient. I am also going through the internals to test components one-by-one as this is a used item purchased recently - to make sure it functions.  Ideally someone will share their notebook notes on step-by-step how to test alot of chips with this tester. The title of the manual I have is "Model 998 Linear IC Tester Instruction Manual" and has schematics / parts list at the end. At the present time I am unfamiliar with how to use this tester. I look forward to using this equipment as it will tell me the linear/analog values rather than just pass/fail. This will help me assess the condition of chips so I can make the decision to replace if readout is weak.

Somethings that are not clear - use of oscilloscope in conjunction with tester? Slider sellings. Use of knobs and switches and dials. I have the 16-pin socket and the book says there are various 14, 16 pin sockets available- I would like to acquire those additional sockets.

Any help or insights on how to use are appreciated. I would like to know step-by-step how to test LM310 and LM311. I hope a kind reader will educate me on how to use this well-made machine (through email or video?). My email address is drviragopete@att.net in case a kind soul will share their insights on how to test.

It is possible there exists a manual (I dont have that) that shows settings for various chips and semiconductors. I do not have any list or settings for various ics at all - only the very thorough (only 1 example in the book) example of testing Fairchild 709 which is quite hard to follow and understand. I purchased this tester in 12/2013 from a USA seller. The testing procedure is from a different era and I am having trouble grasping the concept. It is probably very easy but I am missing these necessary insights.

This IC Tester was purchased used from a USA Seller in 12/2013.  This is my IC Tester #10

Update 12/2013 I have ordered a NTE909D IC which is sealed in its original plastic bag - never used. I will use that 14-pin IC to go through the book's instructions for testing 8-pin 709 Op Amp. Due to the 14-pin rather than 8-pinout I will need to figure out which pin and slider switch needs to be used for this IC for proper testing. I noticed many other sellers of 709 chip or can package ic - the prices are skyhigh. I instead ordered this chip from RadioShack online for $3.60 w/free shipping and is a cross reference for the 709 Op Amp 14-pin edition and is a real bargain pricewise compared to sellers of other brands of 709 Op Amp. I will need to figure out the pin settings and make notes on the side of my book page - so I use the proper pinouts for the 14-pin chip.

ABI Digital IC Tester Chip Master Compact

This tester was purchased used and was mfg in United Kingdom on 2005 and has ROM version 2.00 which is the most current version for this model. It runs on 6V DC at 300ma (I disagree with this voltage as I think it is not correct- I think that the TVS was either 5v or 6V as my best hunch so connecting 9v would blow it out - which is most likely what happened to the previous owner. Some chips on this board have a max rated capacitor of 6V) by using an AC Adapter  (I do not have this) or with standard 4ea AA alkaline batteries. This model of tester is rebranded/branded under at least 1 other namebrand. Some models have a rs-232 port built-in which allows for user added chips and are considered the "Professional" series due to the ability for users to program their own test routines for unknown chips. My tester does not have this rs-232 port and I will use the built-in chiplist only. I see a downloadable firmware update on the ABI website for this model. I will check the firmware version and update it if needed. Hand-typed chiplist is shown in orange color on the right hand side "ChipMaster" I see some similar models advertized as being IC Tester / Identifier which refers to its ability to search for many but not all IC chips inserted in its ZIF socket. This is my IC Tester #11

I purchased this tester used 12/13 but the seller sent a non-working tester - the following files show how I got it to power up it and now works. Maybe it will help someone with a similar issue. I suggest only running this tester on batteries or its original power adapter. Do not use any ordinary AC power adapter - that is what the previous owner did and it blew out the tester. It now works well after repair. I may someday add a 5v internal voltage regulator - but for now it is un-modified except for the removal of the blown 5v or 6v bilateral/non-polarized TVS surface mount component (my best guess at what it was) which was causing a 390ohm short across the supplied power input. For now I am using it only on batteries - until I locate a replacement SMD part and possibly modify it later-on with a voltage regulator.

Update 12/15/14

I believe that fuses and TVS are both protection devices but TVS responds substantially quicker in nanoseconds rather than fraction of a second. TVS is much more INTOLERANT of too high voltages or surges or even micro second interuptions in power. When the TVS blows it is not an OPEN. It is a high resistance ( 390ohms in my case) short between the + and - Fuses are INLINE with the power. TVS is placed across the power. If a fuse blows - it opens and does not allow power to reach circuit, If TVS blows - it creates a high resisitance short - if the power source is not removed - the TVS heats up substantially getting hotter and hotter and hotter and in my case - I found a charred black board. Why didnt they use a voltage regulator such as 7905 or 7805 ? Possibly for power consumption reasons they chose to do it this way- putting the voltage regulator inside the AC power adapter rather than inside the tester? I dont have the AC adapter.

Update 12/15/14 (continued)

I caution you to NEVER connect an ordinary ac/dc adapter to this unit. It is my opinion that the part that was found to be blown on my own used unit - that part is a protection device with a very small tolerance for deviance in supplied power. It is intended to blow this part - if a non-specified power supply is connected.

Heed my advice and only use batteries. It is my hunch that should the original power supply go bad - this can also happen. Play it safe and use batteries on this tester.

Incomplete Views of Comparator Cards & Untested (Use this info at your own risk):i

 My Basic Component Testing Notes

How to basic test Varistor 2-pin (round disc looks like a 25cent coin)

Basic test using a Multimeter set to diode test. There should be no reading "OL" for a good varistor. In otherwords - a good varistor it apears to be open just like a blown fuse. No continuity between legs Jan2016

How to basic test Thermister 2 pin (round disc looks like a 25cent coin)

Using multimeter set to Continuity. Should give a reading and beep for a good one. If no beep and no reading then bad. Common reading for thermister on TV board is 0004.3 to 0006.5 but varies with model.

Square black Sometimes marked "PTC" looks like a relay in TV boards - but only has 3 legs. Test legs 2 and 3 using multimeter continuity test. Common values are 0004.3 to 0006.5 but can vary with model of PTC. If no beep and reading then bad.

A bad thermister can cause a TV to refuse to power on. Jan2016

Miscellaneous Notes

DLP lamp replacement (brand new) for Toshiba TV has no continuity when tested on a multimeter - it is an arc lamp. A bad lamp looks exploded and element inside the glass outer shell module is blatantly obvious shattered. The outside shell prevents the shattered pieces from spraying everywhere- it contains the shrapnel. I saw no glass debris inside the set. Jan2016

Bridge Rectifier 3-phase used in grid tie inverters SQL50A and SQL100A have 5 pins. Some solar vendors are selling unmarked clones with + and - reversed beware. Good part should have + and 3 pins looks like diodes. Also - and 3 pins looks like diodes. Blown will look like a continuity at any given internal diode - or show open. 100A is much bigger in size than 50A and would not fit in case. 1 vendor was selling SQL50A at 1200V and others selling at 1000V. I chose 1200V 2-pack from China and was a good part. Much heat needed to replace it due to heatsinking 100watts soldering iron. I added Plastidip coating of soldered joints.  Symptom load dump always on - short between load port screw terminal and other 3-phase screw terminal caused by shorted SQL50A (1 bad diode inside). Jan2016

________________________________________________________________________________________________________

I own 13ea Professional Integrated Circuit IC Testing Machines - Each Tester Tests a multitude of Integrated Circuit chips.

These machines are useful for testing and perform very well. Some chips are unique to each machine - so I have provided columns of data for reference / data.

I have also included my own notes so I can refer to this list when testing the chip - for example some chips require the use of an adapter board and my own list helps me when testing.

Some of my testers have "Loop" fuction where they continuously test the chip - cycling and looking for intermittant problems and glitches in IC chips - which helps pinpoint bad IC chips which have intermittant issues. Some tests can take 1 second and other tests 80seconds and other tests can be run continuously for as long as the chip is plugged into the socket.

Some of these testers can identify unmarked IC chips as it compares the chip to its built-in list of chips / databank / database using the "Search" function.  

Why have so many testers?

It isnt sufficient to have just one tester. When I check an IC chip to see whether it is a good chip - I test it on multiple testers - as many as I have that will test that IC. See some testers may PASS that IC chip and one or more testers may FAIL it. Well which is the correct diagnosis? I build a list of FALSE PASS or FALSE FAILS and have a pretty good idea on which ones (tester to ic compatibility list) to disregard for certain ICs as there isnt 100% accuracy in any tester. If ALL of my testers PASS the IC the certainty in that IC is very high. If any of the testers FAIL a chip it may be a weakened or bad chip or borderline pass/fail chip (or a defect in the tester itself where the data was entered crrectly in its ROM or EPROM truth tables) Also each tester has its own threshold for what it considers pass/fail which may differ from other testers' threshold.  ALL are good testers and all contribute greatly to the confidence level in knowing whether the IC under test is a good one and worthy of being used in a circuit.

A blown IC chip will FAIL on all of my testers. Not all bad chips are Blown. Some bad chips are just weak and may actually PASS on some testers. A bad chip will FAIL on one or more testers. Every tester I own pulls-its-own-weight and has caught some bad chips that the other testers didnt catch. That is why I value having as many "second opinions" as possible. Even brand new IC chips - sometimes are defective and should be tested before use. Weakened chips often cause a circuit to cease functioning- a weak chip upsets the math that was used when designing that circuit. Only looking for Blown chips - is not the answer to all repairs. It is important to replace Blown parts and weak parts. It takes skill to know when a part is good-enough. If it fails any of my testers- that IC is not-good-enough - even if the other testers PASS it (With the exception of a known truth table defect with that particular chip/tester.) Each tester has its own testing strategy and parameters it looks for.

You should not look at it as - which tester is the best? ALL testers are good and when used as a team as one tool - can catch IC chips which are bad or weak. All testers use a different testing method and parameters. If I relied on only one tester - some bad / weak chips would go undetected.

The more testers I use - the higher the level of confidence in the diagnosis.

An Analogy of A Drivers License Test - relating this to IC Tester

I'm elaborating on why each IC tester is valuable. And you should not think of IC testers as being better or worse - than each other. I value each and every tester that I own. All of them contribute to the confidence level of that Chip being good.

Lets say that each IC tester is like each test you are given when you go to to renew/obtain your drivers license. You may be given some tests 1. Written Test, 2. Behind the wheel tests A Parallel Park B Seatbelt C Speed Limit D Use of Blinkers D Braking E Merging into traffic, etc too many to list. If you expect to get your drivers license but you failed to use your blinkers - you flunked no matter how well you did on any other tests.

Each IC tester uses a different testing strategy - each maker of the IC tester has his/her own idea of how to go about testing the IC to make sure it works. Lets call IC tester #1 a parallel parking test. Lets say the IC test OK or PASS for parallel parking - is this IC good - probably yes. But I will still test that IC on all of my IC testers on-by-one and every once in a great while - I will find that the chip - that has passed every one of my testers - but one. And that chip FAILS on one tester. So somehow the test that the IC tester gave it - did not hold up to scrutiny. I VALUE THAT - GOOD CATCH and it may be the difference between finding that intermittant or hard-to-find problem. I hope the Drivers License analogy makes this clearer. It is not that the chip FOOLed the other testers - that chip passed the Drivers License Written Test, It used its blinkers correctly, it merged and changed lanes correctly. But it failed when it came time to parallel park - so to speak. It was a good catch and replacing that IC chip will be beneficial.

Sometime a chip will FAIL on one tester and PASS on all the rest. It is not always on one tester model. Sometimes another model will catch an error. It is always on a different tester. All of these tester pull-their-own weight and contribute greatly to catching those hard-to-find problems or glitches in circuits. I am always on the lookout for a new IC tester to add to my daily-use equipment. How often does this happen - maybe one out of every 200 -2000 chips (as found in used equipment being troubleshooted) and I have tested thousands. I save these bad chips - they are valuable because they can be used to scrutinize an IC tester purchase. So the bad chip that cannot "parallel park" but is able to pass the "written test" and successfully "merges lanes" now becomes a tool to scrutinze a newly purchased IC tester added to my collection. I have about a dozen bad chips like this - all of them trigger a FAIL response from a totally dfferent tester. I mark these "bad" chips so they do not get reused in a circuit. 

If a person emails me or phones me and asks, "so which IC tester is the best one." I'm telling you right now - you missed the point. The point is that all IC testers are good. They must all work together as a team. All ICs must be tested on multiple testers - as many as possible. A good chip will pass all IC testers- uless there is data entry error in that tester for that particular chip- which some of them have this. And I make note of this - so I know when at the results of the PASS or FAIL is due to a data entry error in the ROM of that Tester. I'm calling this "experience" in understanding what is being displayed.

I know of no-one else in the world who does this.

Intermittant chips

When I find a chip that FAILs on that tester - it generally continues to FAIL on that TESTER - when doublechecked or triplechecked. Even more rare is a chip which will give an intermittant error on one tester - and then you ask yourself - hmm thats strange - did I just see that? An example is my ISI SEM Microscope repair notes (click on the link at top of page to see more about this) regarding a Digital Capture Card. If in doubt - replace the chip and make note of it.

Dr Virago Pete

Phone (847) 454-7858 after 7pm daily

email drviragopete@att.net

Illinois, USA

My assistance is not free - reasonable fee - call or email to inquire.

My Notes about TTL Digital Logic Chips etc

7400 Series Chips usually have the following ratings and specifications printed on the chip (For example 74LS51 or 74HC85 ...)

STD, L, LS, S, H, C, HC, HCT

Temperature range up to approx 160degrees F

5400 Series Chips usually have the following ratings and specifications printed on the chip (For example 54H01, 54C86 ...)

STD, L, LS, S, H, C, HC, HCT

Temperature range up to approx 300degrees F

(5400 series chips are considered the"military specification version" of the 7400 series family of chips. The main difference is temperature rating is vastly higher and rated to survive in a hotter environment. Not all 5400 series chips are rated at 300degrees F - check the datasheet on that particular chip/mfg as some differ.)

Note 5400 series chips and 7400 series chips are generally interchangeable except for temp range is different. (Some exceptions to this may exist)

Most of my Testers are for Digital IC Chips. I can test a few Analog Linear Chips Also- refer to lists (below).

Some chip mfgs have their own numbering system but the chip itself is compatible with a standard chip model - cross reference to standard ICs.

A few of my testers require adapters for certain chips - but most of these same chips do not require an adapter on another one of my testers. By simply using a different tester for that chip - very few adapters are actually needed - because for that chip - there exists another tester which requires no adapter - in all but a few cases.

While all of my testers test mostly the same chips - there are substantial differences in the lists - some testers skip certain chips. All of my testers have a unique set of chips they test and each one handles the testing process differently. When verifying a chip - I try to test it on as menay testers as possible - noting the result for each tester.

For example chip 75L60 can only be tested on the "Chiptester CT-2" as the test is unique to that tester.  74255 can only be tested on the YBD as the test is unique to the tester. 74H61 can only be tested on the GUT as the test is unique to that tester ...

For example 7400 can be tested on all of my testers

What Do the Letter Codes Mean?

74 = Standard TTL

74H = High speed TTL

74L = Low Power TTL

74S = Schottky TTL

74LS = Low Power Schottky TTL

74AS = Advanced Schottky TTL

74ALS = Advanced Low Power Schottky TTL

74C = Metal Gate (Pins are compatible with TTL)

74HC = Silicon Gate High Speed (Pins are compatible with TTL)

74HCT = Silicon Gate High Speed (compatible with TTL)

***Some of the above may not be interchangeable and

check tester before plugging in as some may not be

able to be tested on all testers

I have included a Bug and Glitch list of IC chips which confuse the testers or give False results. False Pass or False Fails and notes regarding special circumstances- see the bottom of this page - at the very end of this page on the right-hand side. Viewer/reader contributions to this growing list is welcome. It is not my intention to knock any tester. I value the "second opinion" of additional IC testers as it adds to the level of confidence that the test results are indeed correct. Knowing which testers give questionable or incorrect results is important. None of my testers are perfect - all of them working together - allows the confidence level to be very high - in obtaining test results and identifying bad parts. It is not intended to say one IC Tester is better or worse. All of them are very good. I'm glad to have them all.