Recently bought some of those remote control sockets so we can turn table lamps on/off.
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There I was, in the kitchen, trying to work out which button controlled which socket.
The nearest handy item to plug in was a large wall wart with an LED indicator.
Plugged that into one remote socket & tried the buttons, number 2 triggered it & the LED came on.
Pressed the number 2 'off button, heard a click, but the LED stayed on.
Plugged wall wart into phone, no charging.
How come the LED stayed on?