HFU HF Underground

General Category => General Radio Discussion => Topic started by: RobRich on November 11, 2020, 0853 UTC

Title: Ethernet As Unintended VHF Radiator
Post by: RobRich 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.

Title: Re: Ethernet As Unintended VHF Radiator
Post by: ThaDood 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.