Tone Meister Messages: 42 Registered: August 2014 Location: NC
Member
Hi, using my first post seeking information on a 200 B1 that is/was blowing fuses. Amp serial number is 59412, no tremolo or reverb. Power amp board is PC703 but I haven't pulled either preamp board so I haven't yet determined exactly which boards they are.
The amp had been sitting for years and was blowing fuses upon power up. Found a shorted driver transistor (38736 = RCA 40409) and was able to source some NOS replacements for all the driver transistors, RCA 40409 and 40410.
There is at least one output that is shorted, so I want to just refurbish the power board and both preamp boards while I have it open. I plan to use 2N3055 replacements unless there is a better choice these days. Please don't suggest the NTE130MP because they cost 20X what I'd have to pay for the 2N3055s.
The main filter caps are good, but I do want to swap out all the tantalum caps on all the boards and all the driver and output transistors, plus the 1 ohm 5 watt resistors. Is there a definitive parts list for these amps, or does someone have parts suggestions for a solid, basic circuit overhaul without going too far overboard? I just want to make the amp functional and reliable.
Any parts suggestions or technical recommendations are welcome.