Thanks for the ideas. I don't think it is IR as there isn't a 'lens' for the transmitter. The black bulge is typical potting compound. But could the device marked D1 be an IR transmitter ?
All IR twitchers seem to be working OK.
Ink cartridges – I do keep them in that sort of area of the lounge as the printer is housed in the TV cabinet.
No visitors (that we know about) for a month or so as we were not at home.
Just looked at an old Canon 560/561 ink cartridge that does indeed have a similar contact pad .
Martin wins the prize – I can't find the cartridge with the missing bit, but here is a photo of another used (non original) cartridge.
Thanks for solving the mystery.
Bob
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