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Transistor Capacitor & Resistor tester

 
Jamie
(@jskinner97)
Noble V-Ratter Registered
Posts: 1572

A HAM Radio friend showed me one of these the other day, Of course I just had to buy one. I can't believe I left it so long!
This little device tells you capacitance, resistance, and tests diodes and transistors at the press of one button. it also tells you if components are O/C. Aswell as giving you an ESR reading. It's brilliant! No more guessing if a capacitor is leaky...

£30 Amazon, Can get them in other places of course. (Without the postage time)
https://www.amazon.co.uk/Transistor-MK-168-Capacitance-Resistance-Electrician/dp/B08TTXVB96/ref=sr_1_1_sspa?crid=170ECYVRGVA34&keywords=Mk-168+Transistor+Tester&qid=1649187997&s=diy&sprefix=mk-168+transistor+tester%2Cdiy%2C296&sr=1-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyS1dZT0c1VEREVTFOJmVuY3J5cHRlZElkPUEwMTM1ODczMUo5QkpXVkxTOUk4MSZlbmNyeXB0ZWRBZElkPUEwNjczNjUxMlkxTU82U09CRFRWUyZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

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Topic starter Posted : 05/04/2022 8:47 pm
Nuvistor
(@nuvistor)
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Posts: 4158

@jskinner97 

Nice unit but there is a but.

A 600vdc working capacitor may only show leakage when a few hundred volts are applied. Most of these work with silicon transistors but germanium have a much higher leakage and may confuse the tester.

 

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Posted : 05/04/2022 10:43 pm
crustytv liked
Boater Sam
(@boater-sam)
Reputable V-Ratter Registered
Posts: 419

Mine was a fiver without the fancy box and does inductance as well. They can be fooled but are very handy providing you accept that what they say is not gospel.

Always short capacitors before connecting or they discharge into the tester and wreck it.

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Posted : 06/04/2022 9:07 am
crustytv
(@crustytv)
Vrat Founder Admin
Posts: 10839

Must admit, I've always been wary of these cheap Chinese testers, good to hear some positive reviews. 

As Frank rightly pointed out, none of these testers, that's including the expensive Peak Atlas range, (see below) can reliably say how a cap will behave when under full rated load. That can only be known by pumping in the rated voltage, which is why I use my bridge for that.

I bought a range of the Peak testers, DCA55 for transistors and diodes, ESR70+ for esr and capacitance checks and the SCR100 for Thyristors and Triacs. The ESR70 discharges caps if you happen to have forgotten, but not rated for seriously high ones, these still need to be discharged but a few 10's of volts it will comfortably sort out.

20220406 095824
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Posted : 06/04/2022 10:33 am
Nuvistor
(@nuvistor)
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Posts: 4158

One of these would have been nice to have in the 1970’s for testing ESR when SMPS were starting to be introduced but hey ho we had what we had.

 

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Posted : 06/04/2022 12:42 pm
Jamie
(@jskinner97)
Noble V-Ratter Registered
Posts: 1572
Posted by: @crustytv

Must admit, I've always been wary of these cheap Chinese testers, good to hear some positive reviews. 

As Frank rightly pointed out, none of these testers, that's including the expensive Peak Atlas range, (see below) can reliably say how a cap will behave when under full rated load. That can only be known by pumping in the rated voltage, which is why I use my bridge for that.

I bought a range of the Peak testers, DCA55 for transistors and diodes, ESR70+ for esr and capacitance checks and the SCR100 for Thyristors and Triacs. The ESR70 discharges caps if you happen to have forgotten, but not rated for seriously high ones, these still need to be discharged but a few 10's of volts it will comfortably sort out.

20220406 095824

I have got an AVO Bridge, which strikes a neon if a capacitor is "leaky" im not sure how accurate this is though? 

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Topic starter Posted : 06/04/2022 8:24 pm
WayneD
(@wayned)
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Posts: 268

This one worked really well and was pretty accurate with electrolytic capacitors until I stupidly forgot to short one out... 🙄 

20220407 110951
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Posted : 07/04/2022 11:13 am
neil1974
(@neil1974)
Honorable V-Ratter Registered
Posts: 601

I've also bought several of the peak testers and they work well. but for me its a case of i wouldn't mind one or more of those to test components before i did buy them but in reality they sit around gathering dust for the most part.

Cheers

Neil.

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Posted : 18/04/2022 1:04 am