Download the schematic from http://blueguitar.org/schems.htm#Fender. The
layout diagram and a couple other downloads for the Blues Deluxe there also,
as is a download for a reverb mod.
--
David
dgminala at mediacombb dot net
** You need to find a schem of the Bandmaster-Reverb Amp AA768.
Shame all the ones Google turns up are illegible.
.... Phil
** This is probably close enough:
http://www.thevintagesound.com/ffg/schem/pro_reverb_aa165_schem.gif
Ignore the Vibrato circuit.
.... Phil
Ron
Ta for that, I have it in the Aspen Pittman Tube Amp vol 3 book which hapens
to be a very clear schematic.
I think I've found the distortion problem, duff 12AX7 socket pin. Remaining
problems are both large Tx only held to the chassis by wishful thinking. And
excess hum (for this owner), bad replacement pots (tagged, not the original
pcb ones). The output matcher had to be moved to accommodate a different
speaker, and not well mounted . Badly blanked off front panel holes for niow
deleted functions.
Other than the cab little seems original, o/p Tx, choke, knobs, chassis ,
valve bases and the jewel pilot lamp holder is about the sum of it
Luckily surplus Rexine in the amp cavity to salvage for where their pet
rabbit has eaten the exposed covering.
Researching the output bottles , nice little page about the company, I like
the "retro" industrial instrumentation
http://www.tubedepot.com/sed1.html
in operation since 1912 they presumably never lost the skill base
Another thing that has remained from the original. That manurey/goaty /
caproic acid smell that emerges when Fender (and other USA-made) amps are
opened to the air in the UK. No one else has come up with another
explanation - so I will stay with the US-patented use of fatty acids from
abattoir sources as a part of the formulation of the insulation of
transformer magnet wire. Then some reaction to UK humidity or UK-specific
microbial action. Not an unpleasant smell , just agricultural, not what you
expect to come from electronic kit.
This amp has a UK made mains transformer replacement so the smell , if from
inside the transformers then from the choke or the output Tx . I
deliberately kept the cab in another room this time , no smell there, so not
horse glue used in the cab making.