Still learning to use my new toy. A while back I built a simple tester to check zero crossing on my MPU. It's just a 24 volt transformer with a bridge rectifier. When I hook it to my volt meter I get 24.36 VDC.
When I connect it to my oscilloscope it shows 38 volts peak to peak. The scope is set to 10 volts per division - counting the divisions I show pretty close to 38 volts.
When I check the 5 and 12 volt supply it shows 5 and 12 volts with a steady line across the scope. (The 5 and 12 volt supply is regulated)
I'm sure the scope is reading correctly - I just don't understand what I'm seeing.
I know the 24 volt unregulated should show the wave form like I'm seeing - But I thought the waves should peak at 24 volts.
Can someone please explain what I'm looking at?
Thanks
Bob
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