Repair job #100

This gorgeous 1972 Fender Twin Reverb is in unbelievable original condition. Cosmetically it is stunning and electronically it is super clean with only minor maintenance issues taken care of over the years. It has that beautiful vintage Fender smell that all amp techs know and love.

That unmistakable smell of a vintage Fender

Who is Mr. Hand?

When it came in it was being readied for sale so a service was in order plus a few maintenance jobs. The badly mismatched quad of power valves was changed out for a matched quad of JJ's 6L6GC's.

The original valves on my valve matcher were giving me:

V1=68mA

V2=30mA

V3=43mA

V4=65mA

V5 vibrato valve was not functioning below '2' on the rate dial and was replaced. A dried out 20uF 500V filter cap needed replacing with a modern Sprague Atom equivalent.

I also replaced the 125V mains fuse with a 250V type. Its not the worst thing I've ever found in an amp's fuse holder but we might as well use the correct type of fuse for the country we are operating in.

Finally. the reverb really wasn't sounding that hot. After removing the tank it was discovered that one of the retaining springs holding the reverb spring mounting plate in a floating position had snapped. One of the reverb springs also had a broken mounting hook. With some parts taken off a donor tank and involving some very fine soldering I set about to repair the tank. After all was put back together it really had not changed dramatically, it being too 'pingy' and not very appealing when pushed up the dial. Just not very 'Fendery'.
After poking around with various tests on the reverb circuitry it was established by tank substitution that the tank itself was just not sounding right. A new Accutronics P-R4AB3C1B tank was ordered in and this tidied up the sound nicely.

A beautiful amp with fantastic originality value,

an absolute pleasure to work on

With thanks to Chris.