The birdies around 14030, 21052, and on the low end of 10M and 6M are
generated by one of the older protocols running on wired Ethernet
systems. The RF is conducted onto the cables and radiated by those
cables. it can be suppressed by ferrite chokes on those cables. If the
cables are longer than about a quarter wave, chokes are required on both
ends. The worst offending hardware can also radiate from its internal
wiring due to poor shielding and poor circuit layout. The only fix for
that is my patented bucket treatment.
The clocks that produce these birdies are stable, but their frequency is
established inside the router or Ethernet switch. If you have neighbors,
you'll hear your them on frequencies slightly different from yours.
Identify which one is yours by killing power to your router or Ethernet
switch to note which one goes away.
Lots of detail on this and how to wind the ferrite chokes in
k9yc.com/RFI-Ham.pdf
and http://k9yc.com/KillingReceiveNoise.pdf
73, Jim K9YC
On 9/18/2017 9:27 AM, Joe Papworth via TenTec wrote:
I hear several around 14030 at my place.
Wired routers can cause it too.
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