Mackvision M2929D1G-62 monitor from a big buck safari game.
picture from the computer is dark and barely seen on the screen. video signal good, verified by several sources.
pressing the button to bring up the OSD shows the OSD nice and bright with all the proper colors.
pulled up the service menu and checked the settings in there...all good. maxed out the brightness and contrast to see the video image. still dark.
OSD has seperate input to video amp, but same drive circuit so the color drive is good, transistors are good, high voltage is good then. It's just the video signal.
replaced the capacitors in line for the RGB (10uF 25v) checked the diodes and resistors (all within spec) some kind of 5V regulator biasing the signal?? 5 volt regulator is good. video amp issue then?
ordered and replaced LM1269NA video amp chip. no change.
what gives? Why would the OSD display perfectly bright video but the video from the computer be super dark?