Sir komrad2236 . . . . .
Individual C board builds also use some hot running metal film resistors on feeding their kine drive power transistors , so check to see if one has not developed a cold solder ring joint and popped open from its PCB connection.
Your efforts were being concentrated on the " C' board / panel . . .with no definitive answer being provided by your tasks.
So, now move back to the cabling found between the main chassis module CN081 connector and its other ends CNC71 at the C module and see if either end is being " connector friendly " in the respect of inserting a straight needle / scribe point / mini jewelers screwdriver end . . . . .into one of its pin 4 or 5 or 6 of its wire connections .
OBSERVE VEWY-VEWEY CLOSELY . . . as it should be possible for that action, to then release a locking pin (s) , which will then let that wire connector release and thus be able to slide / pull out of its plastic surround housing.
ONE CONNECTOR EXAMPLE . . . . .
Here there are two . . . .but sometimes only one spring out tab . . . . on the bottom side of this connector is used.
If a spring out tab is pushed in at the arrow point (s), it should let the connector and its wire, be able be pulled out of its housing.
If not being sprung inward in that process, then it can be inserted in another connector position, and then have it snap out and lock into that new position.
Then if you will pull the GREEN drive wire connector and preferably the RED drive wire connector , swap their positions.
Then hopefully you will THEN have some GREEN video information and expected loss of all of the RED video information . . . . . on your next view of the test pattern foray.
Thus, you need to look back to IC001, backwards, to troubleshoot, as being your potential problem area.
Furthermore, back at the input of IC001, you have the option of inputting a SCARP signal into J401 from a companion inputting device to use its RGB information as another viable input test source .
73's de Edd . . . . .
BUT . . . . I'm being selective . . as I work my way down aisles, I am holding a large
cereal box covering it up, until just before I come upon any PRIME candidates.
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