Dave Cole dave at nk7z.net
Sun Nov 24 13:58:25 EST 2019

Hi Dave,

Your link for the presentation was in a separate email...  Feel free to 
pass it around...

The problem with your RFI solution is you had an inside person... While 
it was good that you did, most folks don't, so the enforcement becomes 
spotty...  I would like the FCC to take a far more active rile in this 
process, but alas, I suspect they won't as we are not on their radar...

I used to deal directly with the FCC, and had good results, but of late, 
I intend to vector any RFI issues through the ARRL, as I try and be in 
compliance with their wishes of being the point group for this sort of 

73, and thanks,
Dave (NK7Z)
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 11/24/19 10:06 AM, David Eckhardt wrote:
> 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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