Peter Hucker wrote:
I have a device which makes a "ping" noise on a piezo tweeter (one of those 10p sized things you get in wrist watches). Is there any way I can connect this output to some LEDs to flash when it makes the noise?

A pair of LEDs in series with one of the piezo wires might work.
Eg:
LED1 Piezo
O----+-|-+--|o|----O
'-|-'
LED2

If it's a piezo with its own oscillator, something like this might work:


LED1 + -
O------|----|o|----O
Piezo

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