Jack1956

Thank you very much for the schematic. I had exactly the same problem, the old modulator was causing checker-boarding on my C128. When I carefully removed the modulator, it fell to pieces, the whole top layer of the pcb lifted and separated! So I built the circuit on vero board, and it solved my video issues. No more checkerboard, and much less vertical bars. I'm now in the process of designing a PCB, for construction of the circuit using SMD's. JP