Standby switch problem...

[danerada]

I have just inherited a 1968 Fender Deluxe Reverb amp from a friend of mine. He has had it in his attic for 20 years!!!! He doesn't even play guitar, he is a drummer...

anyway - the tubes seem to be in Standby all the time. How can I bypass the standby switch to test out whether that is the issue or not? It has been about 14 years since I have done any component level work and I feel like I am thinking through lead. Anyway any assistance would be greatly appreciated.

Dane Rada

[danerada]

Also - does anyone have a schematic and a wiing diagram for this amp?

[stokes]

You must be able to open the amp and test to see if the switch is operable.To do this you must check to see if you have about 450 vdc on the output of the switch,if you do then the switch is okay and the problem is elsewhere.To check,with the switch "off" you will get high voltage at one terminal and nothing at the other,when you flip the switch to "on" you should get high volts at both.If not just get a replacement switch.

[Jag]

www.schematicheaven.com

It's been up and down for the last month or so but was up last time I checked (yesterday).

[stokes]

The Fender Amp Field Guide is a good source of Fender schems.Its at www.ampwares.com/ffg/index.html

[danerada]

It is not the Standby switch. The tubes seem to be in permanent standby...Do you think I need to replace the tubes?

[52 Bill]

I don't understand what you mean by "permanent standby". Could you explain a little better? Does the amp pass signal? Are the power supply voltages within the normal range? Do the tube filaments light up?

Help us, to help you.

[danerada]

The tube filaments light up, but not completely. The entire filament does not light up.

[Don Moose]

The tube filaments light up, but not completely. The entire filament does not light up.

You can't SEE the entire filament of any tube I can think of.
Unless you mean that the filaments of some tubes do not light.

[Enzo]

If i read it right, his problem is that the tubes light up, but no sound results. So it acts as if it were in standby.

I'd be looking for missing high voltage on the B+ line, or an open speaker or broken connection to same.

[danerada]

I will check the connection and such....thank you...

sorry for all of the questions, but I am new to tubes.

[danerada]

It turns out it was just the speaker cable!!!! Man do I feel stupid. i can't believe I overlooked the obvious...connections!