"John Woodgate" wrote in message news: snipped-for-privacy@jmwa.demon.co.uk...
) about 'Help
to the 555 timer.
capacitive sensor is so simple, - just a few turns of
50 turns of thin wire wound on it. Keep a low-valueI'll just expand on John's answer, with which I agree.
Without considerable care in its construction, an inductive pickup may well function as a capacitive pickup anyway. For what the OP wants to do, those few turns together with a very simple limiting network would be much easier.