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Old 5th May 2019, 7:25 pm   #89
buggies
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Join Date: Jan 2009
Location: West Lothian, UK.
Posts: 760
Default Re: Turntable Stroboscope

Well I braved looking at it.
If the timebase is set to 5mS/div (can't quite see the switch position) then that looks like just 50c/s hum pickup from floating input or missing ground somewhere.
Might also be a much slower signal but check for pickup first?
You previous scope pics (about post #54 from memory) looked fine for digital logic so no logical reason for this to be different - apart from miss-connection somewhere.
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