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My New Hobby - Stereo Receivers
#29

I am not aware of anything like it - I used almost exclusively Ge transistors back in the USSR and they are still abundant there and are used in amateur practice and also in most semiconductor portable radios. Not ever saw one transistor going bad due to that kind of things. Overload - yes. Never saw a Ge transistor going bad for internal reason. (actually never saw a Si transistor do that either).

What's more, the power Ge transistors (Soviet П4, П210, П215, П208 and П207) as well as low power ones (MП40 (PNP), МП37 (NPN)) were used extensively by military.

Ge transistors are not without quirks - they work at lower crystal temps (about 85C vs almost 170C for Si), but they do in fact have triple the motility of electrons/holes and the length of run of both charges, as well as half the bandgap.

So Ge devices provide much lower Vf dropouts than the best Si (like Schottky diodes) - 0.3V for diodes vs 0.45-0.5 for the lowest Vf Schottkies (low voltage types).

Ge is more expensive than Si, and Si is convenient. Those were the reasons for ditching Ge transistors. But, in a country like the former USSR they are in such abundance and the prices are so close to junk, they are used extensively and many audiofiles appreciate them for what they can do.

So, "uniformely" in my experience is not even close to the reality.


Messages In This Thread
My New Hobby - Stereo Receivers - by Ron Ramirez - 01-11-2014, 03:41 PM
RE: My New Hobby - Stereo Receivers - by Eric T - 01-11-2014, 05:09 PM
RE: My New Hobby - Stereo Receivers - by morzh - 01-11-2014, 05:14 PM
RE: My New Hobby - Stereo Receivers - by Jayce - 01-11-2014, 06:55 PM
RE: My New Hobby - Stereo Receivers - by y2kbruce - 01-11-2014, 07:08 PM
RE: My New Hobby - Stereo Receivers - by Jayce - 01-11-2014, 08:30 PM
RE: My New Hobby - Stereo Receivers - by morzh - 01-12-2014, 12:01 AM
RE: My New Hobby - Stereo Receivers - by w4rtc - 01-14-2014, 05:05 PM
RE: My New Hobby - Stereo Receivers - by shaler78 - 01-14-2014, 09:41 PM
RE: My New Hobby - Stereo Receivers - by Arran - 01-17-2014, 12:35 AM
RE: My New Hobby - Stereo Receivers - by morzh - 01-17-2014, 09:51 AM
RE: My New Hobby - Stereo Receivers - by morzh - 01-17-2014, 10:31 AM
RE: My New Hobby - Stereo Receivers - by morzh - 01-17-2014, 11:00 AM
RE: My New Hobby - Stereo Receivers - by morzh - 01-17-2014, 12:56 PM
RE: My New Hobby - Stereo Receivers - by Mondial - 01-17-2014, 12:56 PM
RE: My New Hobby - Stereo Receivers - by morzh - 01-17-2014, 01:07 PM
RE: My New Hobby - Stereo Receivers - by morzh - 01-17-2014, 08:40 PM
RE: My New Hobby - Stereo Receivers - by Arran - 01-18-2014, 01:15 AM
RE: My New Hobby - Stereo Receivers - by Mondial - 01-18-2014, 12:30 PM
RE: My New Hobby - Stereo Receivers - by morzh - 01-18-2014, 03:33 PM
RE: My New Hobby - Stereo Receivers - by morzh - 01-18-2014, 08:06 PM
RE: My New Hobby - Stereo Receivers - by morzh - 01-18-2014, 09:26 PM
RE: My New Hobby - Stereo Receivers - by Mondial - 01-18-2014, 10:17 PM
RE: My New Hobby - Stereo Receivers - by Arran - 01-18-2014, 11:13 PM
RE: My New Hobby - Stereo Receivers - by morzh - 01-19-2014, 12:12 AM
RE: My New Hobby - Stereo Receivers - by codefox1 - 03-25-2014, 10:58 AM



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