Testing transistors for gain/leakage, help?

Frequently asked question on transistors: types, substitutions, how to test, use and misuse them.
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mictester
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Post by mictester »

phibes wrote:How is the LCR? That's been on my list of junk to buy for a long time...
It's excellent. It's really useful for those unmarked junk box capacitors!

One caveat: you have to avoid connecting it to charged capacitors! Just short the terminals before you test.
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JVanDe7
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Post by JVanDe7 »

Got the Peak Atlas today and it's the cat's pajamas!! Really glad I bought this thing. Thanks gang!
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mictester
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Post by mictester »

JVanDe7 wrote:Got the Peak Atlas today and it's the cat's pajamas!! Really glad I bought this thing. Thanks gang!
It's a real time saver. I now have three of them - one on my bench at home and two in my work locations. It's one of those "how did I manage before I had one?" things.
"Why is it humming?" "Because it doesn't know the words!"

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JVanDe7
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Post by JVanDe7 »

One question though, I've read the section in the manual about leakage... but I still don't understand how to convert the measurement they give you into one that we use around here. Example - 130 hFe with leakage of 75.

The Peak Atlas gives a leakage measurement that is more like 0.63 or whatever, I think.

Other than that it is extremely helpful and useful and quick and marvelous. Hook those sweet little clips up to the legs, hit the button and in 6 seconds you have a whole bunch of useful info at your fingertips. Beats the hell out of building a test circuit and doing, gulp, MATH! lol
Not to mention looking up datasheets to find pinouts, etc. No longer need to do that.
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Post by IvIark »

We usually talk in microamps (for instance a leakage of 300 is ok for a Fuzz Face), the Peak shows the leakage in milliamps (0.3)
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Post by JVanDe7 »

Thanks man! And thanks for all your sweet-ass vero layouts on your webpage/blog. Seriously. I pretty much always go straight to your site for any layout I ever need and they work very well.
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Post by IvIark »

[smilie=a_goodjobson.gif]
"If anyone is a 'genius' for putting jacks in such a pedal in the only spot where they could physically fit, then I assume I too am a genius for correctly inserting my legs into my pants this morning." - candletears7 - TGP

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Post by JVanDe7 »

Well I was using the Peak Atlas again yesterday, but this time for a new reason...
I was modding a friend's Big Muff Pi, swapping the clipping diodes for LED's instead.
So I hooked up the LED to two of the Peak Atlas' leads, so I could confirm the anode/cathode (just to be sure).
And low and behold, when I pressed the on/test button, the LED started flashing. So it was actually really helpful because I thought I had red LED's in that baggy but they turned out to be white ones. And of course the Peak Atlas told me the forward voltage as well but it was an unexpected perk that the LED flashed 4 or 5 times quickly, which allowed me to know which color it was.

I love this little bugger more and more every time I use it.
“Walk tall, kick ass, learn to speak Arabic, love music and never forget you come from a long line of truth seekers, lovers and warriors.”
― Hunter S. Thompson

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