> SO - anybody tried this or can suggest any useful circuit ideas?

Could you use a canned IR receiver, use a fast control loop to adjust
the IR send level to keep the receiver on the edge of receiving, and use
the IR send level needed as input signal?

Wouter van Ooijen

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Van Ooijen Technische Informatica: www.voti.nl
consultancy, development, PICmicro products

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