Vox AC15C1 tremelo pulsates

[OldGoat2022]

I have a 2012 Vox AC15C1 and there is a loud pulse when the tremelo is turned up. The pulse is the same speed as the speed setting. What should I test to find the source of the of the pulse/clock noise?

 

[SnorkelMonkey]

I have a 2012 Vox AC15C1 and there is a loud pulse when the tremelo is turned up. The pulse is the same speed as the speed setting. What should I test to find the source of the of the pulse/clock noise?

Edit: Just looked at the schematic. That bias wiggler tremolo can be hard on tubes. Try popping in new or known working output tubes and see if that solves the issue.

 

[GotA24Fretter]

The usual diode across the Depth pot trick should work. Cathode to ground.