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Re: transistor ID?

1/15/2001 11:32 PM
Re: transistor ID?
Joe, this is the first time I've used ge trannies and now wish I had hunted some down before.  
The radio has no ID as to the year but judging by the size of the components [ some res are an inch long etc] I'd guess they are mid 60's.  
Cheers Ken.
1/16/2001 2:01 AM

people what was the collector voltage on the Si? I use a 4.7k emitter 100k base to ground and a 220k with a 1meg pot base to +9 with a .0068uf cap. The pot is to adjust the Bias. I tend to like the sound with the Bias at 7.2 to 7.5 volts with the Si. If one does not want to use a pot use a 470k base to +9. Yes the Ge is different than the Si the Si seems to be very sensitive to bias setting, thats why most of my effects have Bias pots.  
I like the "sound"of Ge add the challenge of a good sounding Si Fuzz,overdrive. For people new here R.G. had a mosfet treble booster circuit posted here a few? years? ago. when the rangemaster was being "rediscovered" here.  
Ken what voltage is the radio VW used 6V until 66 If I recall.
1/16/2001 3:27 AM
silis and breadboard
Hi Gus, Thanks for reminding me, we should not judge the sound of a sili in a ge device if we don't get the bias up hotter. I will breadboard a new RM with a bias pot and try the silicon trannies agin, and report back  
A good friend of mine loaned me a breadboard, big one, with the jumper kit , gonna have some fun now.
1/16/2001 4:43 AM
Re: transistor ID?
Gus, the radio appears to be 6v which I guess makes it pre '66.  
As for the bias resistors I used a 100k and a 10k trim pot and just tuned it by ear. I also socketed the tranny and tried all the trannies I have and found the AS300 that has a gain 72hfe sounds spot on.  
Cheers Ken
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