This board is a Teletype transmitter board. It performed the parallel to serial conversion for a serial interface to a terminal. It required a W076 to convert the TTL outputs to Teletype 20ma current loop. This board is an early version, the blue IC's are only seen on a few early board and have date codes of 1968. The board also had a regular pattern of pads over the entire board with track leadouts to connect traces to. This was probably to make the early hand layout easier. The M700 timing generator ( 45K) shows the later style with pads only where IC's or other components are installed.
This board cost $150 in 1970.
Back of board ( 74K)
Back to Previous page All of M series PDP-8/I board information and pictures