Quote from: teemuk on May 21, 2012, 01:46:29 PM
I wouldn't advice going overboard with the capacitance. Too much of it and the inrush will begin to blow fuses. Use caps that have equal or higher voltage rating than the caps you are replacing. For capacitance, get something that's in the ballpark of the old part.

If the old one was, say 500uF, don't use a 1000uF cap but maybe a 470uF, 520uF, or 560uF.

As for unobtanium germanium transistors. If they die replace with silicon and reconfigure the bias circuit. You probably won't notice much difference except for a huge improvement in reliability. R.G. Keen has written some good stuff about this issue concerning Thomas Organ solid-state Vox amplifiers. The good news: The information is for most parts interchangeable since you likely find a very similar design from these amps.

Schematics and layouts..? Heck, if you really need them just spend a few hours to sketch them out. With these kinds of amps it's still humanly possible without a microscope and without having to spend weeks into the process. If you choose to take that path then post the sketches here (or to the Internet in general) so that in the future there actually will be some information and technical documentary about these amps to help other guys like you.

yea i could get a sketch of it and upload it here. pictures of the wiring too would help others. i no how had it is to do something without a layout or schematic. but it will be a little bit (few weeks) got lots of projects right now.

thanks for all the input everyone!!

yea i think im going to gut it and build a fender tube amp into the head, maybe a Princeton?

i just pick up today 2 Sunn 2000s heads and 1 sunn 2x15 cab and a 1979 Fender Bassman combo 4x10. (pics for proof)

so im all set with amps right now so I'll probably set it a side till i feel like building something. lol

you think i can replace all of the 700uf 50v caps with some newer axial maybe 1000uf 100v?

yea it is really clean i kinda like the sound.

i'll just try to fix it maybe keep it for awhile, post it on craigslist and if someone wants to give me 100 bucks for it its theres. 

but i'd like to get a pedal and nice cab and try it out see how it sounds then.

found a loose wire going to one of the input jack resoldered and im getting some sound but its really really faint.

hard figuring these types of things out without a schematic/layout.

hmm...tried it out with a cap i had laying around 800uf 100v. channel 2 still doesnt work .

so should i sell this amp or do you think i should salvage it for parts. im planning on building a fender champ and a few other tube amps. and i could use most of the resistors and caps.

but i really dont wanna salvage it maybe i should sell it and someone can fix it and have a super cool rare unique clean sounding amp.

should i? would that make channel 2 sound any different from 1?

its very cool to hear what people have to say about this unique amp.

it seems pretty well built but looks like its been opened up a few times and some joints resoldered but all is well and sounds pretty good besides the scratchy volume.

any ideas on where to get a matching (or close to matching) 700uf 50v capacitor?


heres a little sound clip with my les paul using bridge pickup(l500xl)
http://www.filedropper.com/rec20120519184016

im already liking this forum! the other forum i posted on i just harassed about me getting shocked.


any ideas on how many watts this thing is putting out?

wow really 1966? if you nees any better pics of any specific parts lmk i can take them asap.

when i first got it the chassis was hot.(tested with volt meter before i touched it because the guy warned me of it(got it for free)). so i wired in a socket from an old power supply for the 3 prong plug. and that fixed the chassis being hot.

it works great and sounds reallyyy good, except channel 2 doesn't work im pretty sure its missing a 700uf 50v capacitor.

hey, new here. just picked up this old 70's solid state amp.

says wildcat bass on the front and on the blue plate it says model number rb-4c / serial number 124

wondering if anyone out there has any information about these or someone i could email for specs couldnt come up with anything on google.