Zenith jumpy picture ...

[old_tv_nut]

It seems odd that it's jumpy on the HDMI to AV converter, which *ought* to have standard NTSC scan rates and sync. But maybe it doesn't. Does anyone here know for sure?

Regarding the bright pic going into the loop through, this is probably because it expects to have a 75 ohm termination, and you are not terminating it, resulting in twice-normal video level.

[rwagoner]

Originally Posted by old_tv_nut

It seems odd that it's jumpy on the HDMI to AV converter, which *ought* to have standard NTSC scan rates and sync. But maybe it doesn't. Does anyone here know for sure?

Regarding the bright pic going into the loop through, this is probably because it expects to have a 75 ohm termination, and you are not terminating it, resulting in twice-normal video level.

There was a known issue with Zenith TVs of the era and something "confuses" the sync system (probably not a great description but that's my memory of the issue). Apparently game console companies had a fix they provided free but it was at the game console level, not the TV. And it happens with AV inputs OR antenna inputs.