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MOSFET turned off - strange voltage drop

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tester43:
Hi,

My Mosfet is handling AC unfiltered half_waves.
When it's on - everything is perfect on my scope.
On the place marked in schematics (see right side of schematics, drain) I see perfect half waves from 0 to 12V as expected when mosfet is closed (conducts current through load resistor).
The issue I have is: when gate of Mosfet is not charged (mosfet not conducting) I see waves with 0 shifted to 0.7-0.8V (approx.).
Probing between zener and it's resistor is visible as attached.
I do not see any reason to have this voltage at the place... what can it be?

T3sl4co1l:
Put a pulldown resistor across the FWB output.

Tim

tester43:
Hi Tim,

Thank you for super quick answer, it's around midnight at my place :)

But.... as stupid as it might sound but... what is FWB?

T3sl4co1l:
Full Wave Bridge [Rectifier]

tester43:
Hmmmm.... How would it work.... Are you saying to put a resistor between + and - of FWB? Or do I get it wrong.
Putting a resistor between + and - would put a resistor parallel to mosfet and LOAD resistor....

Do you have any idea what is this 0,8 that I see on scope?

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