[RFI] Radar Engineers RFI Analyzers

Scott Yost nm8rmedic at rocketmail.com
Mon Dec 24 14:20:45 EST 2012

Actually, there is a device which you MUST track by its
noise signature – the Sling Media Homeplug Ethernet device.  It uses a homeowner’s house wiring – and the
wiring of every other home sharing the power distribution transformer – to
broadcast its ‘wifi’ signal.  A single
unit, in one home, will radiate from every foot of wiring in every home on the
same transformer.  
DF’ing one with my National HFDF showed signal –
everywhere.  There were peaks and nulls
of course, but it originated from every home and outbuilding with AC power wiring.  
Since it is an HF signal and by design has no VHF component,
going higher in frequency to precisely resolve its location is not
possible.  You have to describe the
device to the homeowner, and then find it by a hard search.   I have samples of its audio (RF) signature
if you encounter this beast and want to shorten your time spent in locating
Description: repetitive at approximately a 2 second
interval.  Fairly regular.  It sounds similar to an electric fence, but
unlike electric fences, it is very frequency specific.  No RFI > 25 Mc.  It is notched to avoid the amateur bands, but blankets the 19
meter and other higher and lower SW bands.  Also there is no component in the AM BCB.
What my National HFDF unit did locate, was a pair of arcing
AC power connections in the attic of my neighbor’s home.  We found the Sling unit almost by accident
while killing breakers to repair the arcing wiring.   Full details in an older post here, from last summer.

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