[BC] P.O.ed by transmission line damage

[Davis, Jack L. KTXL]

Message: 13
Date: Tue, 24 Jan 2006 13:13:38 -0700
From: Alan Kline <akline at netins.net>
Subject: Re: [BC] P.O.ed by transmission line damage
To: "Broadcasters' Mailing List" <broadcast at radiolists.net>
Message-ID: <6.2.5.6.2.20060124131318.040cbd08 at oldradio.com>
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I've been up to North Peak a couple of times, years and years ago, 
and it still amazes
me that it was possible to build the 2 TV transmitter sites up there.

The old channel 42 site, the first of the 2, has to be the smallest 
TX building around.
Barely large enough to contain the RCA rig, a rack of processing 
equipment, and that's it.
Literally.  To access the front panel of the TX, one needed to roll a 
sliding door one way
or the other.  The engineer was actually standing *outside* the 
building while working on
the front panel.

Absolutely terrific view, though, on a clear day--the ocean to the Sierra...

ak

At one time channel 42 was owned by the same guy I worked for in Sacramento
and we used to go over there and help them out. That transmitter was one of
the ugliest installations I ever saw.  Imagine building an RCA 2 Klystron 55
KW transmitter in a lawn shed!  There was a sliding door on the shed that
covered the front of the transmitter.  When you stood in front of it you
were actually outside.  We pulled one of the klystrons one time and it
started to rain and the entire klystron and the magnet assembly got soaked.
Imagine working on 23 KV DC outside in the rain!  The water pumps were
actually underneath the heat exchanger and you had to crawl under it to get
at the valves and plumbing.  The RF system was so tight in the ceiling you
had to find someone skinny to crawl through it to get at the reflectometer
heads for a power calibration.  The equipment rack was on a hinge so you
could swing it out of the way to get inside the transmitter cabinet.  I
don't have any idea who installed that rig but they were really ingenious as
to jamming the maximum amount of equipment in a small space.

On the other hand several times we drove through the fog and rain to get
there and when we got up on top it was bright and sunny.  The peak would be
above the clouds and you had a magnificent view of the Sierra to the east.
It could very easily be 20 or 30 degrees warmer on top than on the road
below. On a clear day you could see the Golden Gate Bridge across the bay. 

The channel 64 transmitter up there was also amazing.  The waveguide run
from the building to the antenna pylon had almost 50 mitered elbows in it.
It ran along the ground and the waveguide followed the terrain.  And then to
make the huggers happy it was covered with brown painted plywood!  I have no
idea what the VSWR was, but there were a few slug tuners in the run.

Between channel 42 and 64 there was a ton of RF up there.  The antennas were
barely off the ground and the field was really hot.  The radio in the truck
would go to a loud sync buzz as soon as you hit the top of the hill.  There
was a diesel generator up there for channel 42 but I have no idea how they
got it up there.  The hut was about 10 feet lower than the peak and they
must have dragged a crane up there to place it.  

PG&E would not service the site so the users built their own power line from
the lower gate up to the top.  There were some really long spans because of
the canyons and vertical rise and sometimes the conductors would romp in the
wind and hit each other.  The power quality up there was marginal at best as
there was a recloser at the bottom that would trip open after 3 events.

The Chief Engineer at channel 42 was the most patient guy I ever met.  Most
would have run away after seeing that transmitter site!  He used to hike up
there several times a year because you could not get up the road.  We used
to haul deionized water up there in 5 gallon jugs and carry them across the
rocks to get inside the compound. Those plastic jugs were really slippery
and you could only carry one at a time and negotiate the path.

Man I don't miss that!

Jack
K6YC