So apparently I got hold of a monitor a while back, when trying to cobble together a computer. I left it in an unused room & forgot I had it.
At some point, a cat got to it & peed on it. I don’t know if that’s relevant, but it happened. I went into the unused room looking for my old scanner, found this monitor. With a fresh coat of cat pee. Sigh.
I cleaned up the case, tried hooking the thing up. OK, it doesn’t go above 800x600. But it works reasonably well, except that it doesn’t read any red input & instead fires both red & green for green input. It shows a world that looks mostly like reality, except all in blues & yellows.
It’s an old Tatung. CM-14S…something. If that makes any difference.
Could be a broken VGA cord. Try wiggling it around at the connections and watch to see if that makes a difference. But I’m betting the cat pee shorted something out if it got into the case.
One bump, in case this is a recognizable phenomenon to anyone else.
Also the observation that it’s interesting to see the world in blue, yellow, & black. I read once (in Omni, so take it with a grain of salt) that dogs’ color perception may be something like that, with two primary colors.
Anyway, I have been using the monitor because it actually works stably, instead of ramping up the light output until everything blurs.
I dunno - no luck with Joey P’s solution? 90% of the times I’ve seen this, it’s 'cause one of the pins wasn’t quite straight when you plugged the end in, and it got all bent over. They break off easily, but if you’re careful to never do that again, I’ve always gotten at least one straightening out of them, thus saving the day. Check both ends of the cable.
If not, the cable might be hooped - wiggle it around or replace it to test.
I’m not sure what the effects of cat wee are on a monitor, but it could conceivably be the problem too.
Back when I got my second computer (used), I upgraded the memory and in the process accidentally knocked something (a jumper or similar tiny piece) off of the video card. I never could find that damn part down in the cabinet. Anyway, after this happened, I lost red as well. Everything had an aquamarine cast to it.
Not all the pins are used by the monitor, so a missing pin doesn’t mean that is the problem. You can get a replacement end in a Radio Shack if needed. The times I’ve dealt with a color signal not getting to the monitor it’s been a pin that was pushed in, or a broken wire.
The pin was pushed in because of someone forcing the plug. A needle nose pliers alowed me to pull the pin back out and it was fine. The broken wire required a new end half way up the cord and was a pain. I knew I was going to have trouble down the road when I got haome, and the cord was built into the monitor. Every monitor I’ve owned with the built in cable has failed and made it useless. Always buy a monitor that has a detachable cable for the input.
I had a moniter that a cat marked, he sprayed both the face and the side. A few months later my vertical control went wacky so I took the moniter apart and found one of the switches behind one of the control buttons on the front had corroded away. All that was left was the plastic stump. It was directly below where the cat sprayed the face of the monitor. I removed what was left of the switch, soldered in a couple of wires and hooked those up to a small toggle switch and I was able to use the moniter again. Shortly after that the moniter acted up again, I took it apart and found some corroded component near where the cat sprayed on the side. I was unable to repair this problem, a resistor and a couple other small metal components were destroyed. I ended up tossing that moniter and buying a new one. Cat urine is very corrosive and if any got inside, it probably did the same to your monitor as happened to mine.
Oh, I need to thank Nanoda. It was a bent pin. A pair of tweezers straightened it out sufficiently, & red (& cyan) returned to the world. Wild.
The sad thing is, I had taken it off & put it back on about 4 times before asking about it here (the first time because it didn’t work with the display settings on the computer). The color problem appeared by the 2nd time. I thought I had looked at the pins, at least when I first plugged it in. But not knowing much about it, I may not have made note of the bent one the first time. But I should have looked.