A lot of older circuit designs (DynaComp, Ross Compressor, etc.) use the CA3080, which is now obsolete and rather expensive. The LM13700 is essentially two 3080s in one chip, and much more affordable. Here's a conversion board to use the 13700 in place of the 3080. Use long header pins, mounted from the solder-side of the board. These can then be inserted into an IC socket in place of the 3080. I'm not the first to come up with the sort of board, but hadn't seen one on perf. So hopefully it will be helpful to some of you out there.