Tube Amp Archive

So, in the meantime, it's back to Uncle Doug boot camp and the Bassmaster for this old retired diesel mechanic. - So much more fun than playing with hydraulics or rewiring dirty machinery as I did all my life.. lol

Thanks to all

I think you solved my problem Stevem - Much appreciated. Despite being a brand new 5 watt metal oxide, r26 measures 265 ohms instead of 220. either way, I get 10.3 and 14.5 volts at junctions A & B instead of 12 and 18 volts.. Yet, I'm reading exactly 26.2 volts at the transformer output - Pretty we...

oops, sorry,, I should get 14v at the RCA and I'm getting only 9.14V

Actually, you might be onto something Stevem.. In fact the voltage at the first BC109 is a tad low at 5.94 V where it should be 7V and I only get 9.14 V at the RCA 40315 where I should get 9 according to the schem.. Then again,, all voltage creep up a tad after awhile Perhaps I have a drifting resis...

All caps are new except for C6 (mustard .1 tone cap). Pan is original. never been tinkered with and in good shape.. Input equals output volume FX on or off.. Only issue is reverb is quite weak and tone knobs barely effective.. Then again, this is a very primitive transistor driven unit.. It didn't w...

Could it possibly be because of the nature of the primitive style PCB on my unit and it's own inherent capacity to dissipate heat VS what might be a somewhat more typical PCB on the later model ??

Thanks Steven.. I have already replaced all the caps. But the reverb is rather weak and the "Color" and "Mix" controls seem completely ineffective. So, I thought I'd look into the transistors.. In fact, apparently, the old Lokfit BC149 / BC109 transistors have a very bad reputation far failure. Howe...

Yes, I guess I get that pompeiisneaks.. I just didn't want to join some group I'm not all that interested in just to turn around and take advantage of their knowledge.. lol

Thanks pompeiisneaks.. I'll wait a few days and see if anyone else has any suggestion. Otherwise, I'll just order that and try it out.. Would be nice to get both transistors from the same source though - Especially at $20 shipping for a $3.00 part..
lol

OOPS! Sorry, I just realized that only this schem as found online for a newer version of the TR-2 has the "heat sink notation beside the RCA 40315 transistor The schem as found inside my older unit does not - Not sure what it means but, nevertheless, the transistor appears to be the same and I reall...

To say that this entire site has been an asset would be an understatement. Otherwise, an old retired grease monkey such as myself wouldn't of had a chance repairing or modifying all those vintage amps I've accumulated through the years in my basement.. But, now, in my efforts to rebuild an old Trayn...