Sean, Germanium is interesting stuff, but it is difficult to get parts. My recommended parts would be the 2N1304 and 2N1305 by Texas Instruments. These devices are complementary N and P and were popular back in the middle 1960's. Another device that was popular was the 2N404. These parts are, of course, American, however there should be some European made germanium that you might get more easily.
I had been working a lot with them in their times.
103NU71, 156NU70, OC71, OC30, OC26, 2NU74, GC511/GC521, GD607/617 and many others.
My advice is - forget them. We were young, but the stuff was horrible
Cheers,
Pavel
P.S. Stone age parts. How about selenium rectifiers? Some hiend power supply?
103NU71, 156NU70, OC71, OC30, OC26, 2NU74, GC511/GC521, GD607/617 and many others.
My advice is - forget them. We were young, but the stuff was horrible
Cheers,
Pavel
P.S. Stone age parts. How about selenium rectifiers? Some hiend power supply?
john curl said:Germanium sounds good.
hehe
we were young .....and now we are old farts
Sir John ;
is there some interesting germanium stage to look for?
<quote> Germanium sounds good. </quote>
I agreed. I am now playing with a Heathkit AA-21D which uses all germanium transistors. It has a problem with one pre-amp channel. So I hooked it up directly to the input of the power amp via a passive voume control. When I first turned it on, there're some crackling sounds which faded away after some time.
The sound is unbelievely clean, tube-like, easy listening... I used a FR125 BLH.
I also remembered the good old sound of 2SB77 (hope my memory serves me right).
I agreed. I am now playing with a Heathkit AA-21D which uses all germanium transistors. It has a problem with one pre-amp channel. So I hooked it up directly to the input of the power amp via a passive voume control. When I first turned it on, there're some crackling sounds which faded away after some time.
The sound is unbelievely clean, tube-like, easy listening... I used a FR125 BLH.
I also remembered the good old sound of 2SB77 (hope my memory serves me right).
john curl said:Germanium sounds good.
Narrow bandwidth, lot of noise, ageing /change of parameters/.
Of course - "ideal" building component
I have an working example of a battery powered fm radio designed more than 40 years ago with germanium transistors and it sounds very good, better than one would expect. It beats virtually every table radio that I have heard for the last 20 years. There are a few exceptions, but they are not made any more, either.
PMA said:I had been working a lot with them in their times.
103NU71, 156NU70, OC71, OC30, OC26, 2NU74, GC511/GC521, GD607/617 and many others.
Care to dig in your archives and show us a glimpse of what you did with them?
/Hugo
Netlist said:
Care to dig in your archives and show us a glimpse of what you did with them?
/Hugo
I am sorry, it was done in the late sixties and early seventies of the last century. No PC drawings, and hand drawed artworks not archived yet. I know that I greatly appreciated when Si transistors appeared on the market, BC series, 2N3055 etc. I would not like to go back to Ge thermal instabilities, noise and ageing. Also, I do not think much about their sound, contrary to JC. Unfortunately I did not save any of those Ge amplifiers. I still have several Si amp boards from middle seventies, and to tell you frankly, their sound is very very poor compared to properly done up-to-date design.
Thanks,
I remember a thread where the Telefunken Bajazzo was discussed and I believe it was John Curl who still had a few lying around.
I think I can find more schematics of Germanium designs in my archive.
I still have quite a few different types lying around.
If someone can start an interesting project with them I wouldn't mind to donate some. I'll make a list of what I have later.
/Hugo
I remember a thread where the Telefunken Bajazzo was discussed and I believe it was John Curl who still had a few lying around.
I think I can find more schematics of Germanium designs in my archive.
I still have quite a few different types lying around.
If someone can start an interesting project with them I wouldn't mind to donate some. I'll make a list of what I have later.
/Hugo
I listen to my HEA 2000 radio every day with pleasure - made in Austria in the early 70ies with Germanium transistors (AC187/188 output stage, etc.). Together with the oval inbuildt Celestion loudspeaker it beats every other kitchen radio I have heard hands down, the Tivoli#1 and other highprice items included. I had to change the elcaps yet, but none of the transistors (I must state the I have found this gem in a pile of junk...)
lohk said:I listen to my HEA 2000 radio every day with pleasure - made in Austria in the early 70ies with Germanium transistors (AC187/188 output stage, etc.). Together with the oval inbuildt Celestion loudspeaker it beats every other kitchen radio I have heard hands down, the Tivoli#1 and other highprice items included. I had to change the elcaps yet, but none of the transistors (I must state the I have found this gem in a pile of junk...)
I believe this was in large part to the fact that at that time they understood how to design a well-tuned loudspeaker/enclosure system that gave good sound, including the suggestion of good bass, from even a fraction of a watt output power. That knowledge (and interest) seems to be forgotten later.
Interestingly, lately it seems that it is rediscovered and taken even further with the Bose waveradio and the Bose IPOD docking system, which, although not being HIFI as we understand it, do produce phenomenal sound including strong bass from a dinky package and low power.
What goes around, comes around.
BTW, I may still have a source for AC187/188 and AD161/162 if someone needs them. No idea about the cost but I can ask.
Jan Didden
Jan,
maybe you are right, but this radio is merly a small wooden box, nothing really tuned or refined. It is surely not the merit of germanium transistors alone, that is definitely true. But I learned in the old days that the silicon ransistors are so much more reliable.
Naively asked: Is is possible that gemanium transistors (cause of the much lower pe transition of only 0.3V) may have lower crossover distortions (in classic AB biased push-pull circuits) than their younger cousins? I remember the first schematics I study with GE transistors were transformer based power amplifiers (phase shifting driver and output) with PNP GE power transistors (most GE transitors were PNP).
I recently found several classic GE transistors in my junkbox, and I will make a NAIM style preamp just to listen to the differences. In the old days transistors were very expensive, so active loads etc. were out of reach probably.
I am not a bit nostalgic but curious, maybe with todays knowledge old things can be looked at a different angle.
maybe you are right, but this radio is merly a small wooden box, nothing really tuned or refined. It is surely not the merit of germanium transistors alone, that is definitely true. But I learned in the old days that the silicon ransistors are so much more reliable.
Naively asked: Is is possible that gemanium transistors (cause of the much lower pe transition of only 0.3V) may have lower crossover distortions (in classic AB biased push-pull circuits) than their younger cousins? I remember the first schematics I study with GE transistors were transformer based power amplifiers (phase shifting driver and output) with PNP GE power transistors (most GE transitors were PNP).
I recently found several classic GE transistors in my junkbox, and I will make a NAIM style preamp just to listen to the differences. In the old days transistors were very expensive, so active loads etc. were out of reach probably.
I am not a bit nostalgic but curious, maybe with todays knowledge old things can be looked at a different angle.
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