The CGS Serge panel had room for one small module, so I added this little mixer. The simple design provides two attenuated inputs, plus a bias offset pot with a switch, with normal and inverted outputs. It’s the only non-Serge circuit in the panel.
It is made from a CGS23 Mixer PC board, salvaged from an overhaul of my Mixer-Comparator module. The comparator IC is left out. The design goal of avoiding wires soldered between the boards and front panel was met by installing MTA-100 connectors. This board also serves as a power input filter for the DUSG board, since that board lacks a standard MOTM power header.
Here’s the wiring.