The Lazy Man's Germanium Tester

[mozz]

I've seen old tube testers have a headphone jack, to test for noise. I think a simple circuit like a range master would suffice. They (Hickok,HP, Fluke) used to make semiconductor analyzers but they still want a good buck for used ones. I'm tempted to make one to measure noise with output hooked up to a wideband level meter, scope and headphones. Usually the noisiest are high gain with high leakage, but not always.

[sinthmart]

In attempts to master the correct measurement of the gain of germanium transistors, I encountered very nasty, some mystical problems. "Resistance of the material." Nervously!)) At first, everything went according to the rules, as written. And then a dead end. Perhaps my digital multimeter broke (I need to check it tomorrow). And I tried to measure the current on an arrow device, but I noticed that the transistor under study began to heat up! And I gave up for now. But, I wanted to ask questions:
1-Tell me, the general opinion is that digital transistor testers are not accurate in measuring germanium, because they do not take into account the leakage current. But I also read that they take this leakage current into account! Please explain, do they take it into account or not? Or does it depend on different models? My transistor tester is already old and I do not remember the model, I do not know the firmware, but based on this data, what can I assume?



2- I read experts who claim that fuzz-faces need transistors without a large leakage current, but for Tone Bender-s, on the contrary, with "leaky" transistors. Do you agree? And so almost any transistors are suitable, the main thing is the gain factor of OT 60-70?

[Kevin Mitchell]

These low voltage tests are good enough for our purpose.
Mozz was implying that ICEO is leakage on your tool. Look up ICEO.

Not to disappoint, but I would encourage you to create another thread to inquire on other questions unrelated to the topic at-hand (my tester). Other than my not being able to answer some of your questions, you'll get better guidance with the bonus of not derailing things here.

[sinthmart]

Kevin Mitchell, I already understand that I have begun to overload your topic with third-party data. Sorry. Thank you for your patience))
+
And thank you for the useful topic.
(my problem with the multimeter has cleared up (the fuse burned out) and I can use the classic method of calculating the gain again and I will try not to overload this topic with my deviations from the main direction)

[sinthmart]

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