For similar reasons I recently ordered a pair of Netgear GS108 switches.
12VDC power and metallic case.
I like the option to run off of heavily choked shack DC (except for the
computer and a couple larger amps my whole shack runs off of the battery
bank/charger).
And a metal case, one can at least be hopeful there is some shielding.
That being said, and inline with W0LEV comments in another message...
I always assume there are idiots in the production chain that are going
to powder coat or similar what should be a conductive seam in an
otherwise shielded product.
safety glasses
dremel with carbon steel and stainless brushes (use SS on alu cases)
90deg die grinder with 3m disks
copper foil tape w/ conductive adhesive
Whenever I get a product like these switches, or a computer case, etc...
I assume the seams will be bad.
I generally take to the garage, break open, grind all the mating
surfaces to bare and apply an o2 excluding grease like no-ox-id.
Plastic cases, seams with poor overlap/etc...those get copper tape.
Alot of cheap brick type switchers get alot quieter when there is a 2.4"
toroid with 12 turns on both input and output cables (or more than one
if needed), _and_ the plastic case has a layer of copper foil.
The copper tape might be overkill for most folks but my shack is 2nd
story above my living room and both are 35ft from my HF antenna so every
bit helps.
Don't know if the GS108s will work for me, I got them due to good
experience with a similar 10/100 netgear model (metal case 12vdc), and I
got those based on a 12vdc metal cased Kingston hub they replaced.
All cables will of course be choked and choked again.
On 3/28/18 22:22, Jeff Blaine wrote:
> In the process of overhauling the shack's wiring, I'm wanting to replace
> my existing ethernet switch with a box that is properly shielded - or at
> least has one with a low emission footprint. Here i'm talking about
> radiation from the box itself - not via the connected ethernet lan cable
> runs.
>
> Unfortunately the houses' home-run location terminates a few feet from
> my shack and so the switch needs to be located there. I can apply
> ferrite / common mode treatment to the power supply and lan cables that
> connect to the box. But I also need a box that is properly shielded
> from a ham point-of-view. The switches I have now are all of the
> plastic-case variety and they all are pretty noisy.
>
> I was hoping someone may have found a "quite" switch that could be
> recommended. Some of the semi-pro (e.g. Netgear home-office rack mount)
> stuff has metal cases -- but I don't know if that actually means they
> are quieter.
>
> 73/jeff/ac0c
> alpha-charlie-zero-charlie
> www.ac0c.com
>
> _______________________________________________
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> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>
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