We have had no problems with any of the basic GigE Netgear switches at any of
my stations, other than making sure to apply a choke to the DC output of the
wall wart (or even better, find a model that runs on 12V if possible). In this
case, we needed POE to power some cameras. That always has a certain level of
risk with it since you’re really at the mercy of the power supply for the POE,
whatever it may be. Whether it’s blind luck or quality EMC engineering on the
part of Netgear, this one causes no problems.
-Gary NA6O
> On Jun 22, 2023, at 4:52 PM, <nlsa@nlsa.com> <nlsa@nlsa.com> wrote:
>
> Gary –
> That’s encouraging! Did you select the Netgear GS116PP intentionally or was
> it luck of the draw that you got an RF-quiet model?
> Best regards,
> Michael
>
> From: gwj@me.com <mailto:gwj@me.com> <gwj@me.com <mailto:gwj@me.com>>
> Sent: Thursday, June 22, 2023 4:20 PM
> To: rfi@contesting.com <mailto:rfi@contesting.com>; nlsa@nlsa.com
> <mailto:nlsa@nlsa.com>
> Subject: Re: [RFI] Netgear GS724T switch
>
> 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 <mailto:gwj@me.com>
> https://na6o.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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