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I am guessing there must be a choke wired between A+ and B+, or at least a resistor, otherwise there is no path for current from the rectifier to the B voltages.
600v film caps are available from a bunch of sources.
C1 doesn't have to be 600v.
If C10 and C11 are leaky, then I'd replace all the film caps, there are only a handful anyway.
When the trem doesn't work, the first thing I'd check is the feedback caps. I suspect C5,6,7 are history, so replace them.
The trem works by oscillating. The signal at the plate of V1 feeds back throug C7, C6, and C5 to the grid of V1. Those three caps and their associated resistoprs form a sort of delay line of RC circuits. The output of the tube feeding back to its input makes an oscillator. if it doesn't oscillate, then the caps are bad, or the tube is bad, or the switch is bad. I vote caps, myself.
As that oscillating signal goes up and down, the tube current of V1 shares cathode resistor R11 with V3. The current through R11 varies as teh oscillation in V1, so the voltage across R11 varies. SInce that voltage is also the cathode voltage of V3, this varies the bias of V3. Si it modulates the signal coming through V3. Tremolo.
SOmewhere between the plate of V2 and the top of the volume control, there needs to be a cap, I'd say. otherwise the B+ from the plate will find its way into the volume control and appear on the grid of V3. I'd suspect between V2 and R8/C3. or possibly in that plain wire going up and over from Treble control to volume control.
600v film caps are available from a bunch of sources.
C1 doesn't have to be 600v.
If C10 and C11 are leaky, then I'd replace all the film caps, there are only a handful anyway.
When the trem doesn't work, the first thing I'd check is the feedback caps. I suspect C5,6,7 are history, so replace them.
The trem works by oscillating. The signal at the plate of V1 feeds back throug C7, C6, and C5 to the grid of V1. Those three caps and their associated resistoprs form a sort of delay line of RC circuits. The output of the tube feeding back to its input makes an oscillator. if it doesn't oscillate, then the caps are bad, or the tube is bad, or the switch is bad. I vote caps, myself.
As that oscillating signal goes up and down, the tube current of V1 shares cathode resistor R11 with V3. The current through R11 varies as teh oscillation in V1, so the voltage across R11 varies. SInce that voltage is also the cathode voltage of V3, this varies the bias of V3. Si it modulates the signal coming through V3. Tremolo.
SOmewhere between the plate of V2 and the top of the volume control, there needs to be a cap, I'd say. otherwise the B+ from the plate will find its way into the volume control and appear on the grid of V3. I'd suspect between V2 and R8/C3. or possibly in that plain wire going up and over from Treble control to volume control.
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