Yesterday my father had the honour to get the 80-Column card to work (we removed "extra wiring" which I will put in the next message in this thread)
we compared dip-switch settings, etc.
Assuming that the card always worked is that my guess is that the TV (SCART / RGB) is the one that fixed it (and my VCR-SCART is not
reading the signals correctly). The other option is the home-made cable (but I checked that a few times with Ralf) and I got a white dot moving
(which looked like a Synchronisation problem).
80-Column card is the device at the right side (plugged into the side-slot of the TI-99/4A) and requires 5V power adapter.
This 80-Col card has been adjusted with a power switch at the front.
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