ADC Mixer schematics

[tschnuckel]

I'm trying to figure out the ADC Mixer board.

Does anyone have info on what the RCA connectors are. I'm looking for labels. I know some are inputs and outputs, but what kind. Are some Aux?
Also I know 4 of the pots are gain for the 4 channels but there is a 5th one? Which RCA(s) does the pot affect?
What does the DIP switch do?

[jbird604]

The DIP switches configure the way the channels are mixed down. That same mixer is used in a variety of models, some requiring as many as six inputs to be mixed down to as few as two outputs. With all the switches off, there is no combining of channels, and each switch mixes one pair. You may be able to decode it by trial and error. It is NOT a binary switch, each switch simply has a discrete function.

Four of the pots serve to send more or less of certain channels into the reverb system (which connects to one of the jacks), and the fifth pot probably adjusts the amount of the returned reverb gets equally distributed into all the output channels.

There were several versions of the ADC mixer board, so if you get the model number off the paper label, I might be able to scan the schematic and send to you as a pdf. The organ itself should have some labels that show which jacks are used and what cable is supposed to be plugged into each one. Unused jacks are indicated by a dash mark in the labels.

[toodles]

The mixing down is done using 2 switches for each channel pair: one switch shorts the unused path to ground, the other mixes the 2 channels; there are also switches to handle 1 vs 2 swell shoes.

[tschnuckel]

John,

ADC AUDIO MIXER
ASSY 904-5803-3
SCHEM 081-5097

[jbird604]

Schematic and controls

Here are the only docs I could find on this. Hope it helps.

[tschnuckel]

Thanks! That helps a lot.