Big Keyboard 2068

A circuit diagram for a “Keyboard Interface Circuit” is printed below. The construction method is your choice. (A PC Board for the cartridge slot is a nice idea) I have not included details on re-wiring a keyboard (see March 85 Listing Pg. 18), but used the connection names used in the March issue. All the resistors are 10K and all of the diodes are 1N914. I did not show decoupling capacitors in the diagram. The circuit I built works fine without them, but use them just to be sure.