On Oct 5, 3:22 pm, mike wrote:
robb wrote:

{Excellent advice snipped}

Stick a transformer from the AC line into the input. Wall wart etc.
Does it look like 60 Hz. or 50Hz. depeding on where you live.
You can check several sweep ranges.

Or: holding a bare wire or unbent paper clip, touch it to the input.
Look for 50 or 60 Hz as appropriate.

Mark


{More excellent advice snipped}