THE CGC COMMUNICATOR
                            CGC #525
                     Thursday, July 18, 2002
                 Robert F. Gonsett, W6VR, Editor
     Copyright 2002, Communications General Corporation (CGC)
  This Special Edition of the CGC Communicator newsletter
continues our coverage of last week's FCC inspection at Mt.
Wilson.  That inspection concerned alleged excessive RF signal
strengths in the KMEX-TV driveway, a location which was
apparently accessible to members of the general public at the
time of the investigation.
  In all fairness, the measured "hot spot" may have little
or nothing to do with KMEX's own signal (we will await the FCC's
verdict on that issue), and our use of the term "KMEX" should
not tarnish the fine image of that station, or its employees.
  HISTORICAL NOTES:  Many years ago, CGC engineers surveyed
the KMEX driveway and found that most of the power density was
created by a single FM station.  That station was advised of the
problem - long before human exposure to RF signals was generally
regarded as a serious issue - and the station voluntarily
incorporated a reduced-downward-radiation design into the new
antenna they had planned to install anyway.  In so doing, the
station significantly improved the Mt. Wilson radiofrequency
radiation ("RFR") environment.  Convincing station managers to
even think about RFR wasn't easy in those days.
  Since that time, a number of stations have installed reduced-
downward-radiation antennas - some incorporating "oddball" but
carefully chosen interbay spacings.  Unfortunately, those good
efforts have been compromised by the fact that many more
stations have moved to Wilson (including digital TV facilities),
and much tighter RFR standards have been adopted by the FCC.
Where we were once concerned about the old OSHA 10 mW/square
centimeter standard for workers, we are now very concerned about
a 50-times-tougher standard for the general public: 0.2 mW/
square centimeter in the 30-300 MHz frequency range, for example.
  ENTER THE FCC:  Today, it is possible that several stations
will be cited by the FCC as significant contributors to the KMEX
hot spot.  Any station that creates 5% or more of the maximum
power density permitted at a given location is regarded by the
FCC as being a significant contributor to the problem, and is
eligible for a citation if the aggregate power exceeds the
proscribed limit, which reportedly was the case here.
  In each case of excessive RFR, the FCC has to consider the
facts at hand in determining whether to issue a citation.  In
the present case, the road serving the KMEX driveway is traveled
by members of the general public, the driveway chain and warning
sign were down at the time of the inspection, and no one
attempted to "shoo away" or warn the FCC inspectors that they
had entered a high RF zone.  Bottom line:  Don't look for an FCC
verdict soon:  The Commission is backlogged with RFR cases.
  Moving now from the KMEX driveway to tower climbing
situations, you can imagine the much stronger signals that
are involved.  The logistics of coordinating power cutbacks at
multiple stations in order to permit tower climbing activity
can be a difficult task, and the extraordinary steps needed to
minimize "downtime" for your neighbors can be expensive, as
many of you know.
  Obviously, life has become much more complicated for
broadcast stations in the KMEX zone because of the large number
of independent operators, the FCC's tough RFR standards, and the
lack of an updated RFR document for Mt. Wilson with
recommendations for specific power cutbacks when climbing
activity is underway.
  CGC #523 reported a tower climbing incident where, after
a power reduction was finally accomplished to permit climbing,
one of the reduced power stations decided to RESUME FULL POWER
operation without warning, and with climbers on the tower
  The incident occurred on Sunset Ridge (not Mt. Wilson) and
the power increase was ordered by a TV network Director of
Engineering (not a General Manager).
  Thanks to Roger Knipp of KDOC-TV for pointing out these
corrections over the phone.  The Sunset Ridge incident is
mentioned briefly at the end of his report, which follows.
The details are fascinating, but not the centerpiece of our
current discussion.  (Perhaps Roger will submit a detailed
report later.)
  Let's return now to the issue at hand:  The events
surrounding the FCC's Mt. Wilson FCC inspection of July 12, 2002.
                      LETTER TO THE EDITOR
  When it became necessary to replace our burned up antenna in
the middle of the Mt. Wilson farm, it was necessary to do a lot
of research in a hurry.  I attempted to determine the significant
sources of RF radiation directed toward the project elevation on
the monopole, adjacent to the post office.  It was important to
me to protect John Hignite's workers because he has been climbing
my towers for over 36 years.  I used a 2001 study done for
American Tower for their new tall tower inferring that it was
essentially accurate given the proximity with the monopole.  It
took several days to get all the contact information and send out
notices.  Adding a couple of new stations not on the study, the
ten stations I advised were entirely compliant and eager to
  On the day of the climb, the RFR alarms were sounding and I
learned that at least one inference from the RFR study was
incorrect.  An FM station using a directional antenna was putting
more energy at the top of the monopole than I predicted.
Fortunately I was able to make contact with the FM Chief Engineer
and he reduced power by 20% for me and the tower climbers went
back up.  On the following day we were advised that the engineer's
superiors were not willing to operate at 80% and that he was
prevented from complying for the additional days needed to
complete the work.  This is only the latest incident that may
have influenced the FCC to look more closely at Mt. Wilson.
I am not certain that KDOC had any special issues that caused
the FCC to visit Mt. Wilson.  It may have simply been the straw
that broke the camel's back, or it may have been entirely
coincidental.  Clearly with the gin poles of two climber's stuck
on the tops of two towers, we were facing gridlock at a time
critical to DTV installation.  Tower Structures was unable to
either go forward or to remove their equipment from the KMEX tower
for months.  All it takes is one non-compliant station to shut down
a crew.  How can we satisfy everybody?  For example, Univision
stations were indicating that the World Cup Games were being aired
in the early morning hours and they did not want to reduce power
for us at night, so we elected to climb in daylight.  Beyond that,
it is just safer to do the heavy lifting in the daytime.  After
all, are we not talking about climber safety?  Tower rigging is
dangerous enough in itself, and in my opinion, we have a legal
duty to these men not to make the job even more hazardous.
  [The venue now shifts to Sunset Ridge.   -Ed.]
  Following Friday's inspection by the FCC, I inquired as to
the duty of the designated Chief Operator of a station in regard
to RFR.  When KDOC removed its antenna from Sunset Ridge, we faced
an unexpected power increase ordered by an out-of-state manager.
The FCC agreed that the local engineer or operator could be cited
as well as the licensee.  Management cannot legally direct its
designated Chief Operator to emit signals contrary to the rules.
The RFR rules are no exception.
  Cooperation among engineers is nothing new, as the ten
compliant stations proved.  We lend parts and advice to our
competitors all the time.  For some reason managements will fight,
perhaps because this is just a highly competitive business.  RFR,
however, is not the battlefield.  I want to express my thanks to
those who participated in keeping our workers safe.  Cooperation
in good faith can work.
  Roger Knipp, N6VU, Chief Engineer, KDOC-TV/KDOC-DT
  Four parties have contacted CGC to report apparent unsafe
recent tower construction activities at one or more sites on
Mt. Wilson (unsafe practices are NOT the norm, by the way).
According to the reports, the workers involved in the incident/s
wore no RFR-protective clothing in an area notorious for high
on-tower fields, had no visible personal RFR monitors, and at
times engaged in unsafe climbing practices including being
un-clipped from the tower structure.
  One party claimed to have pictures of the event "somewhere."
Another party indicated it was "an out of state tower company"
presumably hoping to get the tower up before they got caught
violating safety rules.  Some of the climbers reportedly wore
shorts and tennis shoes at times.
  So, what do you do if you see suspicious activities like
these in the future?
  (1)  Consider approaching the crew chief and ask to see
  and discuss his or her RFR safety plan, and the power cut-back
  call list.  Perhaps the chief knows nothing about RFR
  compliance, but would be willing to learn and cooperate.
  (2)  If you need to contact someone on the outside, would the
  FCC be the best party to call?  Specifically who should be
  called, and will they respond promptly?  Would it ever be
  appropriate to contact OSHA?  These questions remain unanswered
  at this juncture, and we are asking for input from responsible
  (3)  Could your station become involved in an injury lawsuit
  because it illuminated careless workers on another tower
  structure?  Could you help insulate your station from legal
  ramifications by reporting suspect tower climbing activity
  when it occurs?  Again, we are looking for input from
  responsible sources.
  Knowing what to do the next time questionable tower climbing
practices occur is crucial.  Incompetent climbing will occur
  There are always holdouts when it comes to RFR studies.
There are those who do not want to participate and pay their
share, and those who elect to take shortcuts when it comes to
RFR paperwork.  However, preparing an RFR report without power
cutback calculations to support climbing activities on ALL towers
should be regarded as an unacceptable practice.  (This is where
the FCC could help by requiring cutback calculations to be
made, and filed at Commission headquarters.)
  Mt. Wilson needs a new/updated RFR study at this time.  That
study should not cost a fortune each time a facility is added or
modified.  Perhaps the users at Wilson can contract with an
outside firm to develop a computer model of the entire site -
with software OWNED by the users group - a model which could
be quickly updated when facilities are added, removed or changed.
  The term radiofrequency radiation ("RFR") too often triggers
fatal images in the public's mind:  Images of atomic (ionizing)
radiation and people "glowing in the dark."  Of course, RF energy
is non-ionizing and for that reason is much different than atomic
radiation - but the point is difficult to convey to the public
once the "R" word is unleashed.
  We have used the RFR term in this newsletter because it is
familiar to broadcast engineers.  However, members of the general
press who may happen to pick up this issue of the CGC Communicator
are encouraged to use a different term, perhaps radiofrequency
energy ("RFE"), radiofrequency fields ("RFF"), radiofrequency
signals ("RFS"), or something entirely new and different, to more
accurately convey the issue on deck without being an alarmist.
                           MORE TO COME
  The number of letters received on the RFR topic were far
more than we expected, or could handle in one newsletter.  Watch
for another Special Edition CGC Communicator soon.  We plan to
publish many of the letters - one right after another - on the
points that have not been summarized above, and which in our
opinion add to the discussion.
  If you have more comments, hold them for now.  The time to
respond is AFTER the next Special Edition is published, so you
can comment on the complete record.
  Thank you for standing up to the plate and discussing RFR
- a very sensitive topic - in a professional manner.  By pulling
together, we can work toward eliminating some of the problems
that are plaguing our industry.
                        SUGGESTED READING
  There is one FCC document we recommend be read at this time.
It is Appendix B of OET-65, and it's only three pages long.  The
Q&A format is easy-to-read and shows what must be done to resolve
a variety of common RFR situations.
  Step 1:  Assemble the following URL into one continuous
  line (if it isn't already), and download FCC pamphlet OET-65
  in pdf format:
  Step 2:  Scroll to the last three pages (Appendix B),
  print them, read them, and implement the required steps.
  Step 3:  Take a well deserved vacation.  You have just
  saved yourself, and your company, an immense amount of grief.
  The CGC Communicator is published for broadcast professionals
  in so. California by Communications General Corporation (CGC),
  consulting radio engineers, Fallbrook, CA.  Short news items
  without attached files are always welcome from our readers;
  letters may be edited for brevity.  E-mail may be sent to:
  rgonsett@ieee.org  or  telephone (760) 723-2700.
  CGC Communicator articles may be reproduced in any form provided
  they are unaltered and credit is given to Communications General
  Corporation and the originating authors, when named.  Past
  issues may be viewed and searched at http://www.bext.com/_CGC/
  courtesy of Bext Corporation.
_________________________    End   _______________________________