Author Topic: EEVblog #1273 - EMC Near Field vs Far Field Explained  (Read 713 times)

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EEVblog #1273 - EMC Near Field vs Far Field Explained
« on: December 20, 2019, 05:50:06 am »
An explanation of near-field vs far-field in relation to EMC compliance testing.
H-field magnetic probes vs e-field electric probes.
Explanation extraction from video #1176
Wideband EMC log-periodic antenna: http://s.click.aliexpress.com/e/DQeIdwZ6
Near field probes: http://s.click.aliexpress.com/e/N5wdxeFQ

 
The following users thanked this post: jancumps, xrunner

Offline VK3DRB

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Re: EEVblog #1273 - EMC Near Field vs Far Field Explained
« Reply #1 on: December 21, 2019, 01:06:05 pm »
Cheaper here... https://www.ebay.com.au/itm/153570679099

$87 Spectrum analyser for the poor man, good enough for use with the near field probes?
https://www.ebay.com.au/itm/Simple-Spectrum-Analyser-D6-with-Trace-Generator-Signals-Ratio-Frequency-Do-K7P3/223621365267?hash=item3410df3e13:g:5AoAAOSwkJxdUbT4

Or a $10 spectrum analyser for the very poor man...

You can also use a good CRO and use FFTs and a wideband RF preamp, instead of a spectrum analyser.

But these days, considering so many products have Bluetooth and/or WiFi, the ideal for many engineers is a spectrum analyser that goes to 3GHz, or better still 6GHz. It is just a matter of time before a NanoVNA equivalent in the form of a decent spectrum analyser becomes available at a fraction of the cost of a traditional spectrum analyser.
 


Offline VK3DRB

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Re: EEVblog #1273 - EMC Near Field vs Far Field Explained
« Reply #3 on: December 23, 2019, 12:58:23 am »
You can also build your own near field test probes... https://interferencetechnology.com/diy-near-field-probes-preamplifiers/
 

Offline ocw

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Re: EEVblog #1273 - EMC Near Field vs Far Field Explained
« Reply #4 on: December 23, 2019, 01:39:25 am »
The Seeed 114990711 / RFEAH-25 20 - 6000 MHz magnetic field probe is just $27.50 at Mouser.
See: http://statics3.seeedstudio.com/assets/file/bazaar/product/RFExplorerRFEAH_25datasheet.pdf
 


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