possibly a standby switch problem

[pbman1953]

The amp is an old Traynor YBA-3A super- sometimes when switching on the amp there isn't any sound. After checking all the connections, which are typically fine, and after re-cylcing the amp the sound comes back.

A tech told that it could be a carbonized stand by. Has anyone faced this?

Thanks

[Willabe]

Check for B+ voltages after the standby switch next time it happens.

No B+ then switch is bad.


                 Brad     

[stratele52]

Check for B+ voltages after the standby switch next time it happens.

No B+ then switch is bad.


                 Brad     

First you must have  B+  BEFORE  the switch

[stratele52]

The amp is an old Traynor YBA-3A super- sometimes when switching on the amp there isn't any sound. After checking all the connections, which are typically fine, and after re-cylcing the amp the sound comes back.

A tech told that it could be a carbonized stand by. Has anyone faced this?

Thanks

Start by Standby switch test .
It could be the fuse and fuse socket too ; Intermittent , but you won't see no heater glow on tubes.

If all tube 's heater glow ;

Checking connections : How you do that ? Just by looking without any skill ?? Old amps could have bad solder in B+ circuit, need to reheat.

Speaker connexion too.

Did you hear a hum at high ( if need) volume  when no sound ?

[pbman1953]

Actually my tech he also  mentioned the B+ and is checking the switch too


Thanks to all!!

[stratele52]

Stand by's can be on the B+ or they can be placed on the B- (read center tap),  in theory, all your doing is breaking the circuit.  
  

On a Traynor YBA-3A switch is on the B- , center tap of power transformer.