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Sportsman1961

212 65

Hi, desperately need schematic for unconverted 212-65. 12ax7 preamp/rectifier(?). Machine redplates both power tubes. Power tranny weepy. Suspect bad coupling caps. (power filter caps?) Does not blow fuses. 120 cycle hum, no output. Can you supply correct schematic? THANKS Found several online, but all are of the transistor model...

RD112
RD112's picture

212 65 Schematic 2100-65

In the "Downloads and Resources" section of this website in the top row banner above, you should be able to locate the schematic with the chassis number indicated. Do you have the 2100-65 chassis?

Sportsman1961

212 65

It is a 2475-65 with tube phase inverter.

mgriffin155

Try this

Sportsman1961

212 65

Hello again. My amp is an 1974 with 12ax7. It uses the 1-65 power tranny. That tranny is obsolete. Am I correct in concluding that the early "center off" power switch amps had a PT that switched on the PRIMARY side? Mojptone has a 100-65 available, but it requires extensive cobbling up of the amp to make work.. There is a German company that claims to e able to supply the correct tranny..any experience with their product? THANKS!!

RD112
RD112's picture

Hammond Transformers

Hammond has replacement Tranny's...I don't know if any of them match...but they have many Fender equivalents...worth contacting them.
They are in Canada...so reputable and not junk.
https://www.hammfg.com

markboettcher

Seen this recently

You're not in NH by any chance? I just looked at the same model with the same problem at a local music store. 2475-65 chassis with the 12ax7. Nothing but hum when turned on. Owner was trying to sell it on consignment. Is this yours by any chance? My first career was electronics repair back in the 70's & 80's, and I offered to take a look at it just for fun.

Anyways, found a shorted cap. Schematic's a bit hard to read, but looks like it was C-37. Cap was a 150uf 50v electrolytic. Cut lead, quick test, good sound, no more hum. Replaced it with sprague, same value. Amp sounds good. No reverb or tremolo, but want to do cap kit and adjust bias before troubleshooting.

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