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[TowerTalk] Site Conflicts, Amateur Protection docs (long)

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Subject: [TowerTalk] Site Conflicts, Amateur Protection docs (long)
From: (Malcolm Clark)
Date: Tue, 21 Apr 1998 12:44:34 +0000
Pat Barthelow wrote:
> Hi Towertalkians:
>         I am getting concerned about "progress being made" at N6IJ. We
> got the N6IJ site from the Government, and it is now managed by our
> Subcommittee (of amateurs,) working under and with the City of Marina.
> Very quickly after it transferred from government ownership to City
> Management for Recreational Purposes, under a lease by the Natioal Park
> Service' "Federal Lands to Parks"
> program,  It is being seen not only as a recreation resource, (N6IJ
> Contest Station, shared with an Equestrian Center, whose trails snake
> amongst the antenna farm poles) , but as a revenue generator through the
> development of the hilltop site wrt commercial radio uses.  The old
> antenna farm, mostly 70 foot poles scattered around the 10 acre site,
> provice great utility for amateur radio antennas.  Some newly planned
> water tanks complicate the development picture somewhat, being 100 ft
> diameter, and 30 ft tall (two of them).  We negotiated future rights to
> place amateur towers amongst the water tanks, to continue our contest
> station development.  Now the talk is about exploiting the ideally located
> hilltop, to generate revenue for the City.  This is/may be a double edged
> sword, as now the interpretation of the government lease is to reqire
> revenue generated on the property to be used for recreational purposes.
> Naturally our interpretation of this is to plow back revenues into antenna
> development/contest station development on the site.  The shared user
> (Equestrian Center) might interpret this as meaning building more horse
> show hardware/riding trails improvments.  The director of parks and
> recreation, may see this revenue as meeting the need for some of this
> money for use in a more general way for all the various parks throughout
> the city.
>         The site is ideally suited for installation of PCS or Cellular or
> 2 way radio equipment.  The site is currently used for HF operating, and
> contesting activities, (recreation), and for providing open space/trails
> for horseback riding.  I could see a future top notch, high power EME
> station there also, using VHF, UHF bands.
> If the site is developed for commercial radio usage, the possibility
> exists that our Amateur radio activities could interfere with some
> commercial radio users of the site.  Also, some commercial uses of the
> site could interfere with amateur radio contesting uses of the site.  If,
> for example, the PCS user of the site, invests the required million
> dollars (just a guess on my part) to install a PCS system on the site, and
> we somehow knock him off the air with our high powered HF transmitters, or
> our 200KW ERP Moonbounce system, the Call to the city manager by the PCS
> company, (or the Cement truck company, or the Paging company, or the taxi
> company, etc...) would bring the following predictable response:
> "I got a call from the (PCS, PAGING, Cement) company, who helps the
> Recreation department with radio site rental revenues in the order of
> $3000/month, and they say you
> guys are making their communications systems worthless."  They want you to
> stop using the hilltop site, or do whatever it takes to not interefere
> with their radio sytems.  What are you going to do about it?"
> (My Worst Nightmare)
> Solutions:
>         We are in the early stages of this evolution, so I am looking for
> expertise that can help us draft a Memorandum of Understanding which has
> boilerplate, and is legally binding, and which does three things:
>         1. Becomes a term and condition in the contracts between the city
> and the Commercial Radio Site users, which defines the existing radio
> environment created by the Amateur Radio Operations, and requires them to
> accept the existing radio environment, and work around it for their uses
>         2. Require the commercial radio users to not interfere with
> existing HF and EME recreational users of the site.  They would have to
> modify, or stop their uses in such a way as to cease interefering with the
> amateur users, at their own expense.
>         3. Require the city to keep the amateur opeators "in the loop"
> early on in the marketing stages, and selection of potential radio users,
> to
> limit those with the highest probability of creating interference, or
> being interefered with the existing amateur radio activity at the site.
> Any of you Tower Talkians  out there know now to create such a MOU
> document?
> Any advice?
> Thanks,

Where to begin?

Your first effort should be to study the terms of the Park Service
lease.  If I understand correctly, the site is federal property leased
to the city for recreational purposes.  If the lease precludes
commercial development of the site--either in plain language or
otherwise--you should be ready to pursue that avenue.

Your organization does not have to get into an adversarial relationship
to the city to do this.  Any citizen can request a copy of the lease
from the Park Service (using the Freedom of Information Act if
necessary).  And if the city is violating the terms of the lease, any
citizen can complain, either directly to the Park Service or through an
elected representative (usually the most effective).  By using a proxy
who is not a ham your club can keep its hands clean if need be.

Assuming development does proceed you may find yourself in the quagmire
of communications site management.  Any time a group of disparate users
try to operate off of the same site a whole host of problems crop up.
Among others, intermod, repeater desensing, security concerns, and
lightning protection issues come to mind.  The more users there are in
close proximity the worse the problems are.  If a high powered broadcast
station is on or near a congested site the intermod problems skyrocket.
If there are multiple high powered stations present, a site can become
almost worthless for repeater operation.

Digital paging transmitters can be a real headache.  Unlike most site
users, the paging operators have little incentive to cooperate to reduce
interference since they don't have any receivers to be interfered with.

Experience has shown that the best way to manage a multi user government
owned communications site--especially an attractive hilltop with lots of
entities clamoring to use it--is the development of a comprehensive site
management plan and the appointment of a site manager.  The site
management plan starts by describing the resource and defining what it
will be used for and what general limitations may be placed upon any
potential user.  For example, the site may be dedicated to land mobile
radio and compatible use.  This would preclude high powered broadcast
stations under all circumstances while allowing low powered services
such as microwave to be admitted on a managed basis.

The management plan is implemented by a site manager.  This entity is
responsible for coordinating all use of the site with all present and
potential users.  If it is done right (emphasis on IF), a thorough
intermod analysis is done for each piece of equipment at the site.  This
requires the site manager to maintain a database of all
equipment--including receivers.  Among other things, the database must
contain all TX, RX, LO, and IF frequencies; antenna types, gains, and
azimuths; etc.  

When a new piece of equipment is proposed for the site an intermod
analysis is done to see if any existing equipment will interfere with
the new, or be interfered with by the new.  If the analysis predicts
interference then the new equipment is rejected.  In some cases changes
to existing equipment may be requested--at the expense of the owner of
the new equipment.

Needless to say the analysis gets extremely complicated if there is more
than a handful of equipment at the site.  For this reason it is usually
farmed out to one of the handful of companies that do this sort of thing
for a living.  The cost is born by the requesting entity and is usually
done in conjunction with any path analysis if microwave is involved.

I don't know how many sites are currently being managed this way. 
Political considerations often work to destroy the plan and geographical
realities sometimes intrude.  For any plan to work all useable land at
the site has to be under direct control of the manager.  If not, someone
is likely to build an adjacent site (if it doesn't already exist) which
will render any plan ineffective.

The most recent site management plan that I have seen was for Santiago
Peak.  It overlooks the Los Angeles Basin and was in draft form when I
saw it.  The site is owned by a National Forest--Cleveland N. F. if I
remember correctly--and you should be able to obtain a copy for the
asking.  If fact it may be worth your while to contact the
Telecommunications Managers for as many national forests as you can and
ask if they have any communications site management plans that you can

Also try contacting the Bureau of Land Management Telecommunications
Manager in Washington D.C.  You should be able to get a phone number by
searching the .Gov. web pages.  Ask him which of his BLM State Offices
have developed plans and how you may obtain them.  I suspect you will be
able to get quite a few.  BLM has hundreds of sites in the western U.S,
and at one time an Interior Dept. ruling required the development of
site management plans.

And now for the bad news:  Ham radio--especially HF--doesn't really fit
well with the analysis program.  Unlike the typical commercial and
government two-way gear found on most sites, ham equipment does not
operate on fixed frequencies--repeaters excepted.  I don't know how one
could run an intermod analysis when the frequency of operation is not

I doubt any sane commercial or public safety user would agree to operate
at a site on a non-interfering basis with ham radio.  If he did I
suspect the first time he was asked to shut down because of interference
you would get political demands for a change in the rules--and I doubt
you get him to shut down at all.

I don't know how much any of this has helped.  Hopefully it will be of
some use.  I left quite a bit out that I wanted to add, but it was
getting way too long.  Any questions, drop me an e-mail. Good luck.

Malcolm KR4HP

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