The elusive Indextron

[dinorhino]

Hi there, I replaced about 60 Capacitors in the tv unit, and around 30 in the diversity unit. All through hole caps.

Today I hooked up my diversity unit to the tv for the first time, I had to figure out the connections for power. There's 2 ground pins, BATTERY, ACC, and REMOTE, all 3 need to receive 12 volts for the unit to power on.

Thankfully the custom cable I made using a old floppy drive ribbon and 26 pin female Centronics connectors was able to handle the current and didn't burn up lol. If you need a cable this is definitely the cheapest and easiest way to do it.

Everything powered up fine, but the screen still shows the same white raster, no menu or anything. When I press the buttons it beeps now so that's a good sign the two units are communicating.

Maybe its not displaying because I haven't hooked up the pins for the "safety harness" that disables the video display when the car is in drive. But I would assume it should still display the menu so you can tune the radio while driving. Ill try that next but I don't know what kind of signal they are expecting.

I would also really appreciate HelloVoltage's input, tell us everything you know please!

If HelloVoltage hasn't already, I intend to reverse engineer the connection between the diversity unit and the tv to see what video signals are being passed. But I need a fully functional unit first.


Update: Something I forgot to mention is that after the white raster gets "squished" half of it turns grey. I discovered that by adjusting the blanking pot on board B the grey part gets brighter or darker. Board B appears to handle the beam indexing and feeds the amplified video to the neck-board and then the cathode on the CRT.

Nothing happened when I tried feeding the B board a video signal into one of its RGB pins either.

I also discovered that by disconnecting the photo sensor board from board B, the pin cushion distortion doesn't happen and the white raster fills the whole screen without changing.

I suspected maybe the diversity unit was not sending video so I tested the connector with my oscilloscope to find what looked like a video signal and I came across one that sort of looked like a video signal and it changed slightly when changing from TV to VIDEO/WM.

Unfortunately while testing I had the tv running for longer than any time before and I heard a small pop and smelled something I can only describe as "too hot electronics" and capacitor juice. So I shut it off and that's as far as I've gotten. I inspected a little and haven't found anything obviously burnt or damaged yet. Checking with a infrared thermometer nothing I can see seems to be getting unreasonably hot, even the vertical output transistor only gets to around 130F

If only there was a service manual available.