Hi Jordan and Bruce - Thanks,
Checked IR receiver +ve pin at 5v 'ish and the output pin at a little less. On application of RCU, receiver output fluctuated DC wise indicating something received and fed to M/Proc.
Guess should have used a scope, and in the days when it sat on the bench I would have done - Now have to find it in a drawer somewhere if desperate, and hope the Lithium battery is still OK, and I can remember how to work it, as on first turning it on thought - "Wow it's all in colour, and full of gizmo's" - Haven't used it since.
Found up a user guide where no mention is made of any code variations as it's a pretty old machine, made when a VCR was still nifty.
Will replace IR receiver as have a drawer full of 'em from scrap - Chris.
Think mention that in God's area of England, root crops have been mostly rubbish due to lack of a summer, but all tree fruit and berries are bearing up rather well, so the post-mending glass is well sorted. Wonder how our antipodean chums sort stuff ?
Later - Replaced IR receiver as suggested - Did the biz.