Gibson GA-50T tremolo doesn't work- Need help/ideas please

[cgoepel]

My latest wayward guitar amp project, the Gibson GA-50T, the tremolo function doesn’t work at all.
My web research says this amp was produced from 1948 till 1955.
I am troubleshooting the section around V7, a 6SL7 which is dual triode. This is an odd circuit so say the least.
The Low Freq Oscillator (LFO), is modulating the screen grids of V2 and V3 which in turn modulates the input signal creating the tremolo effect.

DC voltage measurement are as follows:
V7A –
Plate: 135 Vdc
Grid: +1.9 to 1.7 Vdc (I know it should be about 0 Vdc, ) depending upon pot setting in cathode
Cathode: .005 Vdc

V7B -
Plate: 140 Vdc
Grid: about .005 to .010 Vdc
Cathode: 1.3 Vdc

The 0.1 uF caps are OK for value and leakage
The 0.22 uF is OK for value and leakage
The dual 0.25 uF caps are OK for value.
Voltages on V7A are the same with both 0.1 uF capacitors disconnected.
I’m thinking that V7A is bad
With positive voltage voltage on the grid, could the 6SL7 get damaged - My tube tester is on the fritz at the moment.

[Jazz P Bass]

You need to get a working meter.
Those Vdc readings could very well be Vac.
The first question that I would ask is : "is the LFO working?"
Is there a low frequency signal going to V3's grid?

Rant: these input tube Trem circuits suck, effect wise.

Maybe that is why bias vary Trem is more popular.

[cgoepel]

Thanks Jazz P Bass,
I have a working meter and tube tester now. The LFO is not working.
I have inserted an external LFO signal from my bench generator to V3 which modulates the instrument input nicely.
I need to concentrate on the LFO.
Does anyone have access to a schematic for the Gibson GA-50T earlier than 1964?

[cgoepel]

Update: I got the trem working again. Several issues were found.
1. I found a wiring error that a previous tech had installed.
2. Cathode bypass caps on the preamp tubes were shot. With no 20 uF caps in the circuit, the preamp tubes could not pass the low frequency oscillator signal.
3. I installed (temporarily) a Silicon Rectifier, 8 pin plug-in type, and the B+ voltages went up by approx. 60 volts.
4. I will be replacing all or most of the wax capacitors as well.

Thanks to those that helped!