Chosen Solution
Hey guys! I recently bought a broken NES and replaced the 72 pin connector, and it worked great! until I removed what I thought was old soda from some pins near the RF chip, turns out I messed up, and my NES shows a monochrome screen for a split second, then goes to black while still playing audio. Does anyone know what the substance is so i can find a replacement and put it back on my board, Thanks!
That sounds like flux to me. It’s used in conjunction with solder in order to make the soldering process easier. But once soldering is finished, it serves no purpose for the circuit, and should be removable without affecting anything. I suspect your display issues may be related to something else entirely. You could try re-melting the solder on those suspected pins to make sure they have proper connection to the board, Or it could be an issue with the new 72-pin connector.
