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previous: Doug I was thinking about trying to buil... -- 11/11/1999 8:27 PM

Re: EF-86 & Dr. Z Route 66 Questions

11/16/1999 10:15 AM
Andrew	Re: EF-86 & Dr. Z Route 66 Questions Hi Doug, I gather a few Gibson amps used 5879 pentodes in the preamp. (GA 40 LP? I think) Here's a schematic for another one of them, the GA80: http://www.obsoleteElectronics.com/The_Archives/GA-80_Varitone.jpg That schematic matched my (pristine) chassis, with the exception of the 100k plate resistor on the 12AX7 of channel2: it was actually 220k, the same as channel 1. Cheers Andrew

11/16/1999 10:15 AM

Andrew

Re: EF-86 & Dr. Z Route 66 Questions

Hi Doug,

I gather a few Gibson amps used 5879 pentodes in the preamp. (GA 40 LP? I think) Here's a schematic for another one of them, the GA80:
http://www.obsoleteElectronics.com/The_Archives/GA-80_Varitone.jpg

That schematic matched my (pristine) chassis, with the exception of the 100k plate resistor on the 12AX7 of channel2: it was actually 220k, the same as channel 1.

Cheers
Andrew