Thanks for your replies and advice. Much appreciated. I've now tried inputing the video to the grid of the TV22's video amp but not getting anything sensible as yet. Horiontal sync very ragged and no vertical lock. Probably not surprising as all I've done to the TV so far is replace the waxies and a few high value resistors. I need to get in there with a scope and have a look at the sync separator. I will continue the saga on
https://www.vintage-radio.net/forum/...d.php?t=143583 .