Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

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



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM
Zenith H725
Ed; One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM
Zenith H725
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM
Zenith H725
The PSU filter cap arrived today (thank you USPS!) so I will work on that later. Meanwhile, I have the dial, speaker...EdHolland — 06:42 PM
Philco 610B oscillator wiring
Thanks Terry. After checking my notes I think I recorded about -10v at the 6A7 G4/control grid. The screen grid (G3 &...Tubester — 05:59 PM

[-]
Who's Online
There are currently 1551 online users. [Complete List]
» 1 Member(s) | 1550 Guest(s)
Avatar

>