For the sake of my own curiosity I built a composite mod and hooked it to my inty. I then fed that to the AV2 Sync on green and it was a no go also. I pulled out my Trs-80 color computer with a composite mod and the OSSC synced right up to that. Comparing the 2 signals (inty and Trs 80) It looks like the inty is missing the pulses for interlaced video. If anyone with the skills wants to work on something with me (while I have this stuff hooked up and it’s on the bench) maybe we could design a new AY-3-8915.