Davoli tube reverb inputs

[MarkusBass]

I'm looking for some help with vintage Davoli tube reverb that I'm fixing. I created the schematic (it seems that the factory schematic is not available) but unfortunately input jacks and input pot were disconnected. The reverb had originally two inputs. I'd like to ask you for your opinion how the inputs could be connected. Could it be as simple as two resistors (maybe 68k) connected to the CHANNEL LEVEL pot and grids of V1 and V2 tied together?
I think that additionally a resistor on the output is missing (something like 470k to the ground). What do you think?

Mark

[Gingertube]

It would be my guess that the top of the input level pot simply goes to the hot of the input jack which is feeding the ECL86 reveb driver, that is, the schematic is just missing one connection line, it does not need another jack.
The 12AX7 at the top is just a tweed mixer to mix the "wet" and "dry" signals.

The 12AX7 triodes and the ECL86 triode could all use grid stop resistors, 10K would be plenty.

Cheers,
Ian

[MarkusBass]

Thanks for the answer. This is possible but as you can see (looking at the front panel) there are two jacks (marked Channel #1 and #2), two din inputs (or outputs) and two XLRs (most probably outputs). What would be the reason that they duplicated all inputs/outputs? Of course, user manual is also not available. I would assume that there were two inputs mixed with simple resistor network (like it is done in many amps).

Mark

[Jazz P Bass]

Here is a schematic of the 500R.

You may be able to suss out what is up with yours by comparing the 500R reverb circuit to your unit.

[MarkusBass]

Thanks for the schematic. Yes, this is exactly how I wanted to do it: two 68k resistors on the input and 1M resistor to the ground. The DIN sockets can be double role input-outputs.

Mark

[Jazz P Bass]

Wasn't this unit considered 'stereo'.

[nevetslab]

I agree with the pair of 68k input resistors & the 1M grid leak resistor to ground at the input tube. My guess is the Channel Level Pot connects to the coupling cap following the input tube, rather then the output of the ECL86 reverb tank driver tube. You're doing the mixing with the pair of tubes sharing common plate & cathode resistors.

[MarkusBass]

Here is how it looked originally. I'm not sure about the second input - it could be connected with a resistor (68k as you mentioned). It's already fixed. I added a resistor to the output - 330k to the ground - to avoid noises when the reverb is switched on and it's warming up.
Thanks for all remarks.

Mark