Subject: Re: [BC] P.O.ed by transmission line damage

[Davis, Jack L. KTXL]

Tower crews are notorious for their "Cowboy" attitude.  A few years ago I
had a microwave relay on the North Peak of Mt. Diablo that relayed a 13 GHz
signal from San Francisco to Sacramento.  This is one of the ugliest sites
to get to in the area due to the fact that the road may not be improved for
"environmental concerns".  The last 50 yards of the road are so steep you
can not see the roadway because the hood is in the way, and when you hit the
top you have to immediately hit the brakes to avoid going over the other
side.  Really ugly!  

The system just failed one day, a complete carrier fail between San
Francisco and the Mt. Diablo receiver.  I made several 90 mile trips between
the transmitter and receiver and could not find any problems.  We measured
power and frequency and swapped out the transmitter and receiver.  I noticed
there was some new equipment in the shack on Diablo and I traced the
transmission line up the tower and it was on the west face looking at San
Francisco.  This was an alleged "professional installation" of an on channel
repeater for a local Hip Hop station.  

I climbed up the tower to look at our waveguide run and discovered that when
the tower crew installed the antenna for the Hip Hop station they apparently
snagged the feed horn in our microwave dish and kinked it about 30 degrees
in a vertical plane.  Needless to say this altered the focal point of the 6
foot dish.  It was hard to see from the ground because you could not move
far enough away to see it; the only view was pretty much straight up.  There
was no way they could have done this without knowing what they had done.
Neither the "engineer" for the FM station or the tower crew ever mentioned
it and we spent a lot of time money and energy tracking it down and fixing
it.  

We had to hire another tower rigger to pull our dish off the tower and
replace the feed horn.  I guess if it had been a 2-way or cellular crew that
did it I would have been a bit more understanding.  But the fact it was
another broadcast engineer and crew it really made me nuts!  So much for
professional courtesy! 

I wanted to go after them for expenses but the owner of my station decided
it was not worth the effort.  The whole thing ended up costing us several
thousand dollars plus 4 or 5 days of down time because we could not get a
tower crew right away to fix it when we found the problem.  

Jack Davis
K6YC