This is a Multimode VCF. Obviously, this was
made on a Vector 3662 plug board. This one replaced the original
VCF that was in the JP2. This one was made using CA3280's, while
the original used CA3096's to make the OTA's. That original one could
have been called thumper. This one worked pretty good. The
big black cylinders at the top are TD401 dual transistors.