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Author Topic: Ethernet As Unintended VHF Radiator  (Read 742 times)

Offline RobRich

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Ethernet As Unintended VHF Radiator
« on: November 11, 2020, 0853 UTC »
Apparently a couple of Raspberry Pi 4s using an un-shielded network cable can suffice for 125MHz transmission of CW up to 100m distance using a decent receiver with a simple directional moxon antenna.

https://lipkowski.com/etherify/

On a side note, the FAA and FCC do not take kind to interference in the VHF air band. YMMV.
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Offline ThaDood

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Re: Ethernet As Unintended VHF Radiator
« Reply #1 on: November 11, 2020, 2004 UTC »
That's a battle with Ethernet cable here on the FM BC band, aviation, and even 2M band. I have ferrite chokes on every one here, as to not wipe-out the VHF Mid and High bands. With DSL internet here, there's no way that I get speeds close to 100MHz here. 10MHz, sometimes. BTW, that's the way Cold War espionage worked by RX'ing leaky data cables from various gov facilities. can still happen today.
“I am often asked how radio works. Well, you see, wire telegraphy
is like a very long cat. You yank his tail in New York and he
meows in Los Angeles. Do you understand this? Now, radio is
exactly the same, except that there is no cat.”
-Attributed to Albert Einstein, but I ripped it from the latest Splatter .PDF March 2025 issue.

 

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