TM500 Liquid Crystal Driver
The (Unknown mfg) Liquid Crystal Driver is a plug-in for the TM500 system.
The unit appears to have two channels.
The main board is very good quality.
There are two "proto" type boards in the unit. One is for fuses. The other has a pair of 74121 ICs on it.
Glenn Little, who owns one of these plug-ins says:
When I got it the edge card connector was damaged, thankfully in a place where there are no used pins. There was one power transistor missing and I can replace it with one like in the other channel. There is also a ground binding post missing, this is easily replaced. The pictures are of the unit as I received it.
The plug-in has controls for PW UPPER and PW LOWER for both channels.
There is also a DELAY and AMPLITUDE control for each channel.
There is a BNC for the top channel only INPUT.
There is a BNC for SYNC. The SYNC appears to go to both channels.
There is a label on the front REL 11, so, maybe there are others out there.
The front binding posts are UPPER OUTPUT, LOWER OUTPUT and GROUND for each channel.
The active backplane pins are 2A, 3A, 6A, 7A, 8A, 9A, 10A, 12A, and 7B. 8B, 11B and 8A are connected. 12A and 12B are connected together. All of these pins are power related, so the only inputs and outputs are via the front panel. There is a keyway between pins 6 and 7.
There are "flying" jumpers between some IC pins with some of these pins lifted from the sockets. Probably still a work in progress.
The front panel is thin aluminum with, what looks like, photo etching for the labeling and shading.
Harmonica connectors are used to connect to the board.
The construction looks good, but not of Tektronix quality.