I'm not sure of the exact date but I think it's prob around 1974 - 78.
The first panel has a dual Negative Slew module, two Programmer modules, and a triple Bi-Directional Router.
The second panel includes a module labeled "Dual 7486" (a ring-mod or dual VCA or both), Sequencer, Dual Processor, Envelope Generator, dual Positive Slew, and dual Negative Slew.
Both panels are unusual in that they don't use banana jacks.
The current 3.5mm jacks work fine with my Eurorack modular setup, though it's very tempting
to convert to bananas. For the moment, I've decided to leave things unchanged.
The power supply still works though it does heat up quite a bit.
Supplies the Serge
Possibly a potential fire hazard ??? I think I will replace it soon with a modern one.
Makenoize Pressure Points & Paper Face Serge