wg 4600 (defender) - red missing

[TheShanMan]

My monitor will show red if I adjust it to blare it over the whole screen, but red images aren't showing up if I adjust to "normal" settings. For instance, I have adjusted everything so the test patterns all appear correct, except red is totally missing. Any idea what might be wrong? Would this be a problem on the monitor daughter card or something? I wouldn't be surprised - RetroACTIVE found a TON of problems on my boards when he fixed them for me, due to moisture, oxidation, and what not.

[Kevin Mullins]

Have you adjusted both the Red DRIVE and the Red CUTOFF on the neckboard?

[TheShanMan]

Yeah, they both ultimately have the same effect - to one extreme I get nothing and to the other extreme I get red everywhere as opposed to red just where it's supposed to be (like the flashing "Williams").

[SirPeale]

Check the red driver on the neckboard first.

Actually...check the input first.  On my Xenophobe I had a problem with disappearing red.  The pin pulled out of the harness enough so it wouldn't make contact. 

[TheShanMan]

I haven't checked that really good yet Peale, but nothing appears to be disconnected. However, I did put defender on the color test pages (one is all red, one all green, one all blue), and compared the DC voltage reading on my multimeter on the R, G, and B pins on the monitor header on the cpu/video pcb side. G and B were both reading about 1.5V but R was not (I think it was near zero, IIRC). So it seems like there might be a problem on my board. I haven't traced it back to the source of the problem yet, but hopefully that won't be too hard.