So managed to get a connection with it. It’s very picky about the 1200/75 connection tho, and will think something in the V.22bis negotiation is a V.23 answer sequence. Had to force the answering modem to only do V.23 and then it worked.
Used the USR V.34 Everything as the answering modem here, connected to a laptop running Linux/Minicom. Unit is outside the frame of the shot (sorry!).
Still can’t get a colour display out of it (don’t have an RGB monitor I can plug it into). RF signal (analog TV) is very messy, seems to have a number of repeats over the VHF low band, and is quite low signal strength according to the TV. Found forcing the TV to expect PAL on the composite input gives the best results.
One other issue: No way to hang up except pulling the cable. I suspect the “Log Off” button might only work in Videotex mode.
Edited to add: More pics below.
Just a pic of all the connectors on the back.
Here’s what looks like inside. Main board is double sided (components on top only as was common for thru-hole), while the keyboard PCB was single sided.
In the top left corner of the keyboard, you’ll see one of the plastic pins that hold the PCB in place is missing. There’s two more (one directly down from it toward the connector, and one to the right of the first one). At least 1 of those is snapped off where the pin meets the case (the stub of the pin was floating around in the case). This is why the advertised pic had the 1 and Esc keys looking all wonky. Space bar is also cracked down the middle.
Plan is to remove the melted plastic from the end of the pins that hold in the keyboard, and see how many remaining pins are intact. Depending on how things look, I may either try and fabricate some new pins (probably painful), or replace them with threads (more likely, even if plastic, with nuts on the back of the keyboard). While I’ve got it off, also plan to glue the spacebar back together, and depending on how it’s constructed, give it some reinforcing, so the glue doesn’t have to take all the strain when the bar is depressed.