[RFI] ethernet switch with shielded case or low emission spectrum

[Jeff Blaine]

I don't need to guess the Ethernet spur frequencies - thanks to Murphy 
they seem to be on MY QRG automagically!!!  :)

73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com

On 29-Mar-18 11:08 PM, Dave Cole (NK7Z) wrote:
> Take a look at:
>
> https://www.nk7z.net/rfi-snapshots/
>
> just below the first image of Ethernet RFI is a list of frequencies 
> you can expect to find Ethernet RFI on...
>
> Also, if anyone has images of KNOWN RFI sources, please shoot them to 
> me off list and I will include them on the RFI Snapshots page.
>
> 73s and thanks,
> Dave
> NK7Z
> https://www.nk7z.net
>
> On 03/29/2018 07:16 AM, Chris wrote:
>> That's what I hear as well...birdies spaced evenly across the 
>> band(s).  Not s9 or anything like that, but still real annoying!!  I 
>> guess that is the price we pay for modern technology.
>>
>> Chris
>> KF7P
>>
>>
>> On Mar 29, 2018, at 8:13 AM, jonie41 jonie41 wrote:
>>
>>> Our ADSL modem is in my shack sitting on top of my computer. I use 
>>> Ethernet to
>>> the shack computer, a four bay NAS and two 50ft runs of CAT5 to two 
>>> other
>>> computers located quite close to the shack. Yes, if I find a quiet 
>>> spot on a
>>> band and it coincides with a birdie, I can just hear the birdie, if 
>>> I shut down
>>> the computer, all goes quiet.
>>>
>>> Could I just be lucky or possibly ignorant of the level of RFI?
>>>
>>> John
>>> VE3KKQ
>>>
>>>> ---------- Original Message ----------
>>>> From: Chris <EZRhino at fastmovers.biz>
>>>> Date: March 29, 2018 at 8:59 AM
>>>>
>>>>
>>>> Hi Jeff,
>>>>
>>>> I've got an ethernet line from a rooftop dish coming into my shack 
>>>> along with
>>>> the other incoming coax lines, and the router was right there 
>>>> behind my shack
>>>> desk.  No amount of ferrite at multiple places along the ethernet
>>>> cable--before the router, after the router, on the power cord, 
>>>> etc.--would
>>>> make any difference on the noise heard on the radio.  Even shielded 
>>>> cat5
>>>> didn't help.  My solution was the run the router away from the 
>>>> shack, just a
>>>> dozen feet or so into the other room, and then use wifi to get 
>>>> internet to my
>>>> computer instead of a direct connection.  Ethernet is a horrible 
>>>> thing for
>>>> RFI!
>>>>
>>>> Good luck.
>>>>
>>>> Chris
>>>> KF7P
>>>>
>>>>
>>>>
>>>> On Mar 29, 2018, at 12:22 AM, 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
>>>>>
>>>>> _______________________________________________
>>>>> RFI mailing list
>>>>> RFI at contesting.com
>>>>> http://lists.contesting.com/mailman/listinfo/rfi
>>>>
>>>> _______________________________________________
>>>> RFI mailing list
>>>> RFI at contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/rfi
>>>
>>
>> _______________________________________________
>> RFI mailing list
>> RFI at contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
>>
> _______________________________________________
> RFI mailing list
> RFI at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>