Faraday paradox revisited,magnetic field rotation question.

[not_a_mib]

A "field mill" instrument might be usable for measuring the electric fields around these devices.  It is essentially the MOSFET electrometer mentioned earlier, with the pickup electrodes either rotating through the field to be measured or periodically shielded so the amplifier sees an AC signal.  This is much easier to detect, and works around charge leakage and drift in the amplifier.

An example design:  http://www.missioninstruments.com/pages/learning/about_fm2.html

[lumen]

A "field mill" instrument might be usable for measuring the electric fields around these devices.  It is essentially the MOSFET electrometer mentioned earlier, with the pickup electrodes either rotating through the field to be measured or periodically shielded so the amplifier sees an AC signal.  This is much easier to detect, and works around charge leakage and drift in the amplifier.

An example design:  http://www.missioninstruments.com/pages/learning/about_fm2.html

Seems like a bit of overkill for a sensor you could build for $3.00.
All these MOSFET sensors still require a reference to detect from no matter how advanced so operator error is a major fail point.

[PolaczekCebulaczek]

ok its time for small update:
I just performed an experiment; rotating neo magnet and mosfet electroscope...
the problem is with rotating magnet, I have to rotate it on bike wheel because current from electric drill is affecting mosfet :/ this thing is really sensitive! so, RPM's were not the best.
Since LED visually is not telling much I hooked up voltmeter across LED to see things better and i did not register anything important, no electric field detected so far, need to build much better contraption for this, high RPM's are needed. 

[lumen]

ok its time for small update:
I just performed an experiment; rotating neo magnet and mosfet electroscope...
the problem is with rotating magnet, I have to rotate it on bike wheel because current from electric drill is affecting mosfet :/ this thing is really sensitive! so, RPM's where not the best.
Since LED visually is not telling much I hooked up voltmeter across LED to see things better and i did not register anything important, no electric field detected so far, need to build much better contraption for this, high RPM's are needed.

I think you might want to modify the electroscope like the diagram I posted so you can adjust the trigger point to within a few millivolts.
Also you could make a temporary connection from the magnet to the minus terminal of the battery to set a common reference point.

Then even a slow rotation should provide enough to trigger the electroscope if in fact the field is rotating with the magnet.

Direction of rotation is also important as one direction would move electrons away from the gate and not trigger the LED.

[PolaczekCebulaczek]

I think you might want to modify the electroscope like the diagram I posted so you can adjust the trigger point to within a few millivolts.
Also you could make a temporary connection from the magnet to the minus terminal of the battery to set a common reference point.

Then even a slow rotation should provide enough to trigger the electroscope if in fact the field is rotating with the magnet.

Direction of rotation is also important as one direction would move electrons away from the gate and not trigger the LED.

yeah, thanks for tips I will try that soon.