KV-1352 Video Input Hacking

The Sony KV-1352 CRT Color TV has no Component or CVBS video input.

However, there is an option enhancement "OPK-103" to add a "V-Board" into the KV-1352 which seems to provide Teletext-functionality. Additionally, the already present cut-out in the KV-1352s back case suggests potentially a SCART connector.

Nevertheless, I could not find hide nor hair about this miraculous "V-Board": there is no place to buy this board, not even hints to its part number, but also no documentation like functional description or schematic.

Therefore, let's try some reverse engineering in absence of the subject ...

= Extracting hints from the KV-1352 service manual

The KV-1352 Service Manual describes in chapter 2.6 adding the option "OPK-103" in the following (functional) steps (I added my interpretation of the effect these changes take on the TV):

1. cut JW2 (wire link) on the M-board
   • this leads to change input level on IC2 (M50120P) / Pin 24 (Mode2) from pulled down to ground to being pulled up, thus changing the remote control receiver from TV-mode to Text-mode
2. new connections:
   1. V1 - M12
      • M12-Signals:
        • n/c
        • GND
        • nDATA from/to remote control receiver controller IC2 (M50120P)
        • nDLIM from/to remote control receiver controller IC2 (M50120P)
   2. V2 - A14
      • A14-Signals:
        • 7 - KILLER
        • 6 - BLK - blanking
        • 5 - HP
        • 4 - SYNC
        • 3 - VIDEO
        • 2 - GND
        • 1 - +12V
   3. V4 - A16
      • A16-Signals
        • 1 - IH-Delay out
        • 2 - GND
        • 3 - GND
        • 4 - IH Delay in
   4. V5 - A11
      • A11-Signal
        • 1 - GND
        • 2 - R
        • 3 - G
        • 4 - B
   5. V9 - F7
      • a closer inspection of my KV-1352 showed that the same connector labeled with "F-7" on the top/component side of the PCB is labeled with "A-6" on the bottom/solder side ??? ...
      • (BTW: same seems to have happened with A15 (solder side) vs A-17 (component side)
      • F7(A-6)-Signals (A-6 reference in the schematic)
        • 1 - GND
        • 2 - GND
        • 3 - n/c
        • 4 - +6V
        • 5 - +14V
        • 6 - n/c