Again, I'm trying to KISS (Keep It Simple, Stupid).
Color Stream #1 (since I can't seem to find the RCA jacks on the A/V schematic for CS2) signal is handled differently. "Y" along with "L" & "R" is still sent to their respective pins of QV01, while "Y" also is sent to QV30 switch IC along with "Pb" & "Pr."
So hook the scope to pin #51 of the Hyper, Input a signal on CS1, switch set to CS1 and see if you observe a signal. Leave scope alone, connect input signal to CS2, switch set to CS2 and see if you observe a signal.
I forgot to mention, that simultaneously, same thing should be being input to IC510 pin #3. Confirm.
Now we'll see if we can observe any signal trying to be output from the Hyper board. It (Y-Out) should leave the Hyper board at Pin #1 and arrive at IC510 at pin #8. Connect scope at Hyper end. Try various inputs. If IS there also try IC510 pin #8. Is switching from SD/HD automatic (dependent on input) or manually set?
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