Help with N64 RGB Mod

A while back I did an n64 rgb mod on an older version of the n64. The specific parts I used was the DIY THS7314 board and for a while it worked fine. But I unplugged it for a bit, and used composite on a crt for a bit. When I tried to use the rgb another time its no just a black screen. The upscaler im using is the GBS 8200 which i know works as I used it with another console and it works fine. I also know the n64 works as it works through composite. Lastly I know that the sync signal is fine, as it recognizes when i pulg in the cable for sync. Any help would be great.

I did one of these mods on a launch N64 as well. Check that the amp is getting power, I guess. Get a multimeter and check for activity on the RGB lines.

When rgb worked before were you using the same scaler?