Use nine pieces of hookup wire (or a piece of
ribbon cable) to connect corresponding points on the I/O Demonstration
Board to the Relay Sub Board. Connect 12 volts DC (smoothed) to the
power input points on the I/O Demonstration Board. Solder in as many
relays as you intend to use, each with its associated LED, resistor and
1N914 signal diode.
LATEST UPDATE: The board is now
designed so that it may be cut in two to make two separate boards, each
with four relays. This should be more than adequate for most purposes.
8 (or less) 12 volt SPDT relays
8 x 3mm red LEDs
8 x 560 ohm 1/4 watt carbon resistors
8 x 1N914 (or similar) diodes
1 x PCB Relay Sub Board