I picked up what appears to be a bunch of base station / Repeater ID'ers. I have no other clue as to anything else that they might be. They're an NPC model 243 - I haven't found anything on the web about them. They are a circuit board mounted in a small box (6-1/2" X 5-3/4"), which is a little smaller than an S-COM 5K, 6K, or similar box, and the box is mounted to a 19" wide rack panel that is 1-3/4" high.
The circuit board has four-Mitsubishi PROMs - with cover labels over the windows, and they've been marked as "1", "2", "3", and "800 Hz". The PROMs labeled 1, 2, and 3 are 28-pin ICs marked MSL2764K and also have numbers that appear to be 82 and 83 date codes. The 4th PROM labeled "800 Hz" is a 24-pin MSL2732K IC with an 83 date code. The circuit board has a connector with a ribbon cable that goes to an 18-pin terminal strip on the back of the box. The front of the rack panel has a small opening for a small circuit-board-mounted speaker, a front-panel hole for a screwdriver adjusted "AUDIO ADJ." pot that's on the circuit board, a green "ON" LED, and a "TEST" push button. There are two - seven position and one - five position DIP switches on the circuit board, as well as several movable 2-pin jumpers. I see several other things on the circuit board like a 3-terminal voltage regulator IC, an LM380N IC, and about a dozen other 14 and 16-pin ICs. Anyone familiar with these units? Or should I just chuck them into the dumpster? Larry