
RF Field-Probes PBS 1 / DC to 9GHz - peter_d_sherman
https://www.aaronia.com/products/antennas/RF-Field-Probes-PBS1/
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avian
These are usually called "near field probes". You can easily make a basic one
yourself with a piece of thin coax [1].

As leoedin mentions, they are useless without some instrument to attach them
to. Ideally a $100k+ spectrum analyzer, but you can sometimes get some basic
readings out of them also with just a cheap oscilloscope + a RF detector [2].

[1] [http://www.emcesd.com/tt120100.htm](http://www.emcesd.com/tt120100.htm)

[2]
[https://www.aliexpress.com/item/32747667435.html](https://www.aliexpress.com/item/32747667435.html)

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peter_d_sherman
"You can easily make a basic one yourself with a piece of thin coax [1]."

Fascinating! Did not know this! But in thinking about it, if all of these near
field probes are actually small antennas of various characteristics, then
technically coax would be an antenna, also... no?

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peter_d_sherman
Disclaimer: Not trying to recommend a product or anything here, just never
knew that RF probes existed for fields from DC to 9GHz... Of course, this is
probably old information for some specialized electrical engineering
professions (I mostly do software... EE is just a side hobby for me, so
forgive the ignorance...). But anyway, I think the ability to detect fields of
any frequency (well, up to 9Ghz!) is unbelievably cool! It gives me ideas for
Star-Trek like devices...

~~~
leoedin
These don't do anything on their own. You need to couple them with a spectrum
analyser - another $1k+.

I've used these for hunting down problems with EMC on a PCB. They're quite
useful, but it's hard to get a good picture of whether the device will
actually fail or not based on the results. Generally if you put one of these
near a switching power supply it'll go crazy, but that doesn't necessarily
mean that the device will fail EMC testing. You really need a far field
antenna with some sort of calibrated source to really know how you're doing.

~~~
e-_pusher
You can still get pretty far with an RTL-SDR attached to them, which can be
had for $25. I have successfully debugged radiated EMI issues with the
combination of these two:

[https://www.amazon.com/seeed-Studio-RF-Explorer-
Antenna/dp/B...](https://www.amazon.com/seeed-Studio-RF-Explorer-
Antenna/dp/B077K2J8H2/ref=sr_1_2?keywords=near+field+antenna+kit&qid=1574714557&sr=8-2)

[https://www.amazon.com/RTL-SDR-Blog-RTL2832U-Software-
Define...](https://www.amazon.com/RTL-SDR-Blog-RTL2832U-Software-
Defined/dp/B0129EBDS2/ref=sr_1_4?keywords=rtl-sdr&qid=1574714580&sr=8-4)

~~~
opwieurposiu
What was the culprit? IME noisy switchers are easy to find, Improper signal
termination impedance hard to find.

