Can't find any info on this amp. Anyone know?

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hpattern
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Re: Can't find any info on this amp. Anyone know?

Post by hpattern »

.25 MFD. Should I replace that one as well?
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martin manning
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Re: Can't find any info on this amp. Anyone know?

Post by martin manning »

No, I'm looking for the power supply filters, the 20uF and 3x 10uF shown on the schematic. You have two 10's in the one can, so there must be a 20 and another 10, or some other combination that adds up to 50 somewhere. For the two tan cardboard covered ones with insulated wire leads, what are the values?
hpattern
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Re: Can't find any info on this amp. Anyone know?

Post by hpattern »

The Large cap below the one I initially described is a 20+10MF 450WVDC.
There are also 2 smaller Astron mini mite on either end of the board. They are behind the board so I cannot see the values.
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martin manning
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Re: Can't find any info on this amp. Anyone know?

Post by martin manning »

Ok, so that's all of them, a 20/10 450V and a 10/10 450V. That's what you need to look for. Start with those and see where you are. The other small electrolytics may be okay and maybe not. There's a good chance the other (non-electrolytic) caps are fine.
hpattern
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Re: Can't find any info on this amp. Anyone know?

Post by hpattern »

Thank you for your help! The site you recommended had the 10+10 cap but not the 20+10. Any other suggestions on where I might find that one?
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martin manning
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Re: Can't find any info on this amp. Anyone know?

Post by martin manning »

I just Googled "multi-section electrolytic" and found this: http://www.dialcover.com/capacitors2.html You could use this guy's 10/10/10 and parallel two of the 10's to make it a 20/10. I know nothing about this supplier, though. Many times you have to get a little creative and make up the compliment in a different way than the original.
hpattern
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Re: Can't find any info on this amp. Anyone know?

Post by hpattern »

Thanks, I'll give it a try. Appreciate all your help!
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Phil_S
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Re: Can't find any info on this amp. Anyone know?

Post by Phil_S »

hpattern wrote:Thanks for the info. I was hoping to keep it as original looking as possible. Would I need to look for ...
They don't make those old style paper covered caps any more. I wouldn't buy any NOS electrolytic caps. You run the risk that they have dried out and won't form up properly, so it isn't worth it.

What some people do is hollow out the old cardboard tubes and set modern caps inside to preserve the look. No one who works on amps is going to be fooled by that, so it isn't a matter of any sort of deception. You might give some thought to that.

Personally, I wouldn't be concerned. I'd just replace the caps. New caps are going to be way smaller. You can probably figure out how to fit in single caps, which is probably cheapest and easiest.

You have a real beauty there. Good luck with it!
hpattern
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Re: Can't find any info on this amp. Anyone know?

Post by hpattern »

Thanks for the suggestions. Much appreciated.
kingdanielm
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Re: Can't find any info on this amp. Anyone know?

Post by kingdanielm »

hpattern wrote: Sun Nov 06, 2011 11:20 pm Thanks for the suggestions. Much appreciated.
Reviving an old thread as I search for more info about these amps. I own three of the 1959 Epiphones- The Pacemaker (EA-50), Devon (EA-35), and Century (EA-25T). All three amps correlate to the Gibson lineup of the same year, with the GA-5 Skylark, GA-8 Gibsonette, and GA-20T Ranger.

Does anyone else know anything about these? hpattern hasn't visited this forum again since he got his information back in 2011. Even over 6 years later, there's still very little information available on the internet about these.
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Phil_S
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Re: Can't find any info on this amp. Anyone know?

Post by Phil_S »

I own a couple of Gibson amps. I've got a GA17-RVT and GA20-RVT. I think the 17 is in or near the lineup you mention, early 60's. The 20 is later, 1965-ish. The ones you mention maybe late 50's. It is hard to know as Gibson retained the designations but the amps changed over time. What is it that you want to know?
kingdanielm
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Re: Can't find any info on this amp. Anyone know?

Post by kingdanielm »

My amps, as well as hpattern's, are unique to 1959 and possibly early 1960. Never marketed in any Gibson or Epiphone print advertisement, so there are no catalogs that feature them. They differ from the Epiphone/Gibson amps of the early 60s. None of these amps have reverb.

In doing more research and talking to more gearheads, it seems very likely that Gibson put this first run of Epiphone amps into production sometime in 1959 as part of a new product line post-acquisition to satiate their need/desire to sell the Epiphone name to dealers. They had the same circuit and features as their bigger brothers, just wrapped in a different package. It's possible that Gibson saw a way to sell a similar amp to dealers without a bigger contractual commitment, all while retuning the Epiphone brand and creating a secondary revenue stream. It's been suggested that the diamond fabric covering was prone to wear and tear at a much quicker rate, and Gibson decided to move on from it quickly, hence the very low production numbers and little to no historical evidence.
kingdanielm
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Re: Can't find any info on this amp. Anyone know?

Post by kingdanielm »

Was anyone ever in touch with hpattern directly? Seemed he was only here for info on the amp and he hasn't been back since. I'd love to know if he still has the amp.
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martin manning
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Re: Can't find any info on this amp. Anyone know?

Post by martin manning »

Not me, but I have seen schematics for the ones you mention. The drawings seem to be original to Epiphone.
kingdanielm
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Re: Can't find any info on this amp. Anyone know?

Post by kingdanielm »

I too, have seen the schematics. I know the amps are out there, but there can't be many.

The only thing that separates them from their Gibson counterparts is the cabinet style and general aesthetic. Circuits match up identically to all 1959 Gibson amps. The Epiphones are just harder to find.
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