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No audio signal after swapping capacitors

I recently tried swapping out 65 year old electrolytic coupling capacitors from a Motorola HS 711B stereo tube amp. After installing the new caps on one channel of the amp, I no longer get an audio signal, just static from this channel. Any suggestions for troubleshooting this? It's not a high value amp so I'm only using Orange Drop caps. There are no markings for polarity so I'm not sure if that's going to make a difference here.
 
Underside of Amp - new Caps.JPG
 
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Can't see nothing wrong, unless there'ss a short to another wire, hard to see, but you probably checked that.
If both channels have the problem, there's something else wrong, not the caps.
Anything else that might have been changed, even inadvertently?
Are you sure there's signal coming out of the source?
Did you temporarily disconnect power, or removed a fuse, and forgot to put back, that sort of thing?
Can you see the tubes glow?
Do you have a multimeter?
Diagnose!

Jan
 
The standard practice is to measure the voltage from each tube pin to ground. Comparing the results from one side to other should show up what might be wrong.

Personally I would bet on either accidentally changing the prior connection or a cold solder joint.

Easy to reheat the bad side capacitor and add a small bit of fresh solder to each joint.

Murphy’s law however is quite clear. The new failure has nothing to do with what you changed!

In the picture it looks like the top 100 ohm resistor is bad. You can test the value with the power off overnight and compare it to the other channels 100 ohm resistor.

The other issue is the bottom left new capacitor solder joint doesn’t look bright and shiny.
 
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Yes, it's easy to be fooled by images but the soldering on both replacement caps just doesn't look good enough, whether it makes electrical connections or not. I imagine that the new work hasn't received enough heat and flux to flow the solder properly and make nice, shiny fillets which show good solder flow and adhesion to the wires etc. If you have used lead-free alloy solder instead of 60/40 for example, that requires a higher temperature which might explain the problem.
 
The originals were "electrolytic coupling capacitors", I thinl not. They are drawn as the old days used to. The ) side is the outer of the winding and the | side is the inner for noise and hum pickup reasons.
They were Paper.
Resoldering/desoldering components, especially Carbon Composition resistors can seriously damage them.
You have two channels, one good one bad. Compare the voltages when on and measure the resistors values when discharged.
 
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