David Eckhardt davearea51a at gmail.com
Sun Nov 24 13:06:53 EST 2019

 have held off writing this since the subject recently came up.  However,
it is time to relate a complaint that we as a club (Northern Colorado
Amateur Radio Club, NCARC) filed some six or seven years ago that worked
out quite amiably in our favor.  The repeater was to support and event a
couple of months in the future for which the county required comm.
support.  The key was to have a known and friendly contact within the FCC
office in Denver, Colorado.

Problem:  One of our repeaters was being 'jammed' by a large and
aggressive (from an RFI standpoint) LED matrix sign.  We found the culprit
by driving up and down South College Ave in Fort Collins with an antenna
and a portable spectrum analyzer (before the affordable SDR's hit the
market).   When we felt we were close, we took the portable spectrum
analyzer on foot with a small antenna, and ultimately, a very short E-Field
probe. The RFI was so bad it could be detected some 15 miles distant and
'through' a couple of high granite 'hills' of which Colorado has many.  It
was BAD!

Once the problem sign was located, we introduced ourselves inside the
business and asked them to turn off the sign to verify that was, indeed,
the source.  Sign turned off, RFI ceased.  We advised the business of the
problem and the FCC rules regarding such interference.   We then determined
the sign installer since the business had no engineering staff - they were
a furniture store.

The sign installer was contacted.  Their response was to have a "ground"
installed at the sign.  Sound familiar??!!

Installation of the "ground" did nothing to weaken the RFI.  The installer
assumed they could do nothing else and washed their hands to the situation.

The club put together a painfully word smithed letter supported with
measured data and sent it to both the business and the sign installer.  The
business, once again, defaulted to the sign installer.

The installer blew off the first letter.  We contacted them on the phone,
again.  They indicated they had installed a "ground" and could offer no
further service in alleviating the problem.

We sent a second letter.  Same responses.

After contacting our 'inside person' at the FCC office in Denver, Colorado,
and explaining the situation and what we had done previously, a third and
final letter was sent out to the business, the sign installer, and the FCC
office in Denver (they knew the letter was coming and were aware of our
previous efforts).

FCC, Denver, issued a letter to the sign installer giving them 30-days to
correct the problem.  The first FCC letter was blown off.  The second
letter from FCC, Denver, was quite specific and offered to levy fines per
FCC rules of causing interference to a properly licensed service.

That finally got some action, but it took a final personal visit from the
Denver office to 'instill some respect" for a government agency, the FCC.
The sign installer got the sign designer involved - engineering - and fixed
the problem, at least alleviated the RFI, to a tolerable level.

Paramount to this success was the FCC contact in the Denver office.  It
took a lot of work and word sleuthing of the letters.  Fortunately, we had
someone in the club who had a relationship with the Denver office as well.

One of very few success stories.

Please have a read of the last paragraph of my QRZ page for some personal
experiences gained over some 35+ years of doing RFI and regulatory
engineering/design and testing.

*Dave - WØLEV*

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