Interesting method to catch oscilations

[yefj]

Hello,in the attached video they catch oscilation using loop antenna, few questions:
1.how can we distinguish oscilations from noise with this loop antenna method.
2.Antenna works on fringing fields,so how exactly this they create this "antenna"
they took a wire made circles and tied one end to center and other to the shielding?
or both ends connected to the central pin?
Thanks.

 

[KlausST]

Hi,

all it does: it picks up magnetic RF field.

It does not destinguish between signal or noise. It´s the job of the user and the measurement device (scope / spectrum analyzer...)

Klaus

 

[danadakk]

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The above might be useful.


Regards, Dana.

 

[D.A.(Tony)Stewart]

These are all near-field probes. you can also short a 10:1 probe with ground clip and plug into spectrum analyzer to look at noise > 20 MHz or coax and magnet wire for higher f.

E-fields will be mutually coupled and B fields enclosed by loop.

 

[danadakk]

Just be sure your portion of ground lead alligator clip cannot
contact powered up parts, hence damage/destroy them.

EMI probes generally well insulated for this problem.


Regards, Dana.