Here’s a benchmark for you on low-RFI (at VHF) ethernet switches. At the W6TCP
remote EME station (144, 220, 432, and 1296), we use a Netgear GS116PP 16-port
POE unmanaged switch. There is zero RFI at this station. It has an external
SMPS adapter that has 12 turns on a mix 31 toroid on the DC line but only to
remove residual noise in the HF bands that might bother the other nearby HF
station. We do not use shielded ethernet cables. I have checked carefully
around all our equipment with a VHF sniffer probe (small loop) and proved that
all conducted emissions are pleasingly low. Ian got himself WAS on 2m in
exactly 365 days, and on 220 in just over a year… Not too shabby.
Gary, NA6O
gwj@me.com
https://na6o.com
>
> Dear friends,
>
> My remote 2m EME system is comprised of a number of modules (SDR,
> transverter, SSPA, plus antenna and ventilation control modules, etc.), all
> of which are linked to each other via a Netgear GS724T Gigabit
> <https://www.netgear.com/business/wired/switches/smart/gs724tv4/
> <https://www.netgear.com/business/wired/switches/smart/gs724tv4/>> "smart
> switch." All this equipment is located right underneath the EME antenna.
> Despite abundant snap-on ferrite chokes and use of STP Cat6 cables
> throughout, there is still considerable EMI from the switch and the Ethernet
> cables connected to it. Is there more that I can do to quiet the switch?
> Alternatively, is there a network switch that is known to be RF-quiet?
>
> Thanks,
>
> Mike, W9IP
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