capacitor voltage ratings

[and]

hi. i have an old, non-working, sentura ii head that needs 2 new caps. The ones in the amp, which are dead, are rated 1000uf at 50volts, but the sentura ii schematic sheet specifies a rating of 30v and 1000uf. Which voltage rating should i put in?? and, does it matter if i use 50s when it specifies 30s??  

also, i am getting no sound what-so-ever out of the amp, and one of the preamp tubes (all of which test good) is not glowing. is this due to the dead caps???  

thanks,
andrew

[Ryan Phelps]

Andrew;
The 1000 uf caps are for the vibrato and, as I recall, part of the reverb circuitry. If you are getting no sound out of the amp, replacing these caps won't help. The voltage rating on  these caps ( 30v. or  50v.) won't really matter as these are filter caps for the solid-state circuit board which doesn't run on a higher voltage than 15v.or so. I think you can get them from Antique Electronic Supply in Tempe AZ.
 If one of the preamp tubes is not glowing, first put in a known working tube in to be sure it's not the tube. If this doesn't help then there is a problem with either the socket or the 6.3v. heater wiring to that socket (the other tubes light up OK?). Try cleaning the socket contacts and re-tensioning them for positve electrical connection. And check the heater wires to that socket for a postive electrical connection too.

Good Luck!
Ryan

[Brian Comnes]

I would also add a safety precaution that you drain any large capacitors before you stick your fingers in there.......If you don't know how to do that, get an amp technician or any good amp book to show you how, its not hard, but you can't play guitar very well after self inflicted high voltage electroshock therapy.