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TOWERS

"Courage is resistance to fear, mastery of fear - not absence of fear." -Mark Twain

Night time

With glove in mouth, and high on a tower, I prepare for a night of work...


The tower is high and I can not afford to climb back down because I forgot something. I always bring two sets of lights and one extra set of AAA batteries. One set of batteries will last the intire night from midnight to 5:30.

Before I start toward a remote broadcast site, which is miles away on a mountain, I stop at the studio, and leave a personal note for the operator. I place a physical note, and a maintenance-picture, on the keyboard. This big piece of paper is the old-fashioned way: an obtrusive, "manual" way. And tells of a real live human-being talking to another real live human-being. The operator still has to use that keyboard to sign on duty, but there is now a note covering the controls. He has to see it.

My control system will not allow operators to apply hazardous radiation to the antenna structures and me; "Me" being the important part. The control system knows that I am on the tower. At the remote site, on the mountain, I select a couple of icons with the mouse to disable the big transmitters. Simple really, just a few "clicks". From this keyboard, I told it not to allow "Automatic-operations", nor remote "Commands-from-operators" in Chico. In addition, this computer told the studio computer in Chico not to allow commands from even being initiated at that entry point either. Two computers, both looking out for my safety. The Chico computer does one more thing: A sign stating that a man is on the tower will be displayed on a monitor in Chico; A reason is always given, as to why the operators do not have control.
I should be safe...
As soon as I am safely down, I will return control to Chico.

Still, I do not stop with just those precautions...
For my safety, I also physically disable the two big transmitters in a way that my control system can not fix. I know of strategic HV breakers that prevent my control system from bringing up radiation. Disabling one transmitter is not enough! My control system knows that there are two transmitters. If the control system is not successful in bringing up one transmitter, then it will start warming up the second transmitter. An "emergency start up seqence" is applied to the second transmitter. And it will be operational in 76 seconds. It is for sure. It is so skillful at what it does.

I can only imagine what would happen...
My system would be vocally iterating words on an outside speaker; as it diligently brought - on line - each Power Amplifier; Each capable of a blistering 25 thousand watts. It is just a vocalization on the outside of the building, a step-by-step cronology, a cold monotone computer-voice. I would be warned of the danger, if I could hear.

Three hundred feet high on a tower, I would not be able to hear the words, so far below. At 80 seconds, it would announce that the 10kw driver was being applied to the Power Amps, and announce that radiation was beginning. Sadly, I would never hear it; Not this far up. The control system would not be able to get full power yet; but still, at only about 40% power - enough to kill me. And diffinity not enough time to get down from the antenna, before body parts instantly overheated. 5 minutes is all it takes for the time the transmitter to reach full power, at which time the SWR overload circuits would be tripping due to my body "in the way" of the radiation. My control system would begin to notify operators that it had a big problem - all to late.

I am wearing the ear lights, worn much like a pair of glasses. Of the two - these I rarely wear. These lights are my emergency lights, and are always tucked away in my back back. My normal light is a single head band incandescent with a quad battery pack of triple-a's. I took almost no pictures of myself on towers. And it is so unfortunate that this picture has the ear lights and not the single headlamp.



This night, I am looking for an air leak. My computer system, down below, and also in Chico, has kept track of the total run-time of the air compressor. The total runtime is 190 minutes per day. Obviously, There is an air leak somewhere. For several days, the air leak has been monitored by my control system; and each day has displayed a warning screen that the runtime is excessive! Each day the operator has had to notify an engineer, and type "ok" to silence the alarm. Also - clearly obvious - is the the accumulated minutes of runtime printed at the end of each broadcast log. No way around it. My control system has made it absolutely clear: I have to fix this problem.


I have instruments to help diagnose the problem... One is a "bridge": Electrical measurements with a DC bridge give a reading of .03 ohms which is ok. This reading tells me the physical integrity of the transmission line is ok.

But there could be more "subtle" electrical problems: Measurements with the TDR show a slight abnormality. And the location is at - exactly - the same spot that I have been suspicious; same spot as last year. Night time, with radiation removed, is the only time that I can climb around on the, normally radiating, structures. No matter how good your warning system, and no matter how good your instruments - you still have to go there.


Some work must be done at night when radiation is absent. When TV broadcasting began in the 1950's, high power transmitters consumed enormous power. For example, a 50KW transmitter with an efficiency of 15% would consume about 200kW of electricity. As a consequence, broadcast stations would not broadcast at night, because the reduced viewership - at this time - would not support the expense. Also, in the early years, maintenance was higher in quantity, time, and expense. Technicians had to have scheduled downtime to keep a station on the air. And night work was absolutely necessary.

Night work was done at the studio too, when essential equipment was not being used. I never really enjoyed night work. I had to sleep in the day. Sleeping in the day is so unnatural. You have to contend with day noises like telephones and vacuum cleaners. Nothing "sparkles". For twenty years I worked nights, and, still, was on emergency-call during the day.
Actually I was on emergency-call at night too. So that kind of makes it - ALL - the time.

Daytime High on a tower... 2006.07.14

It is not all bad...
Some days are wonderful. The air is clean; And I am away from all the stress of the office. Being high on a tower is stressful too, but it is a totally different kind of stress. I think I would choose "tower stress" to "people stress".

Removed 2002.06.05 VCD MOVIE MPG 4MB as requested

TDR display of a diplexer 1999

TDR picture of a diplexer.
There is nothing wrong with this particular diplexer; all diplexers will paint complex pictures.
An engineer must have a "before" and an "after". I maintained accurate pictures of all tower components and major antennas. I was in charge, I choose this action, and I was the first engineer to do this.
TDR displays are such complex wave patterns that comparisons of pictures of good devices to those of questionable devices is the only to way . (Actually, that is not quite true: If a transmitter can be held on air long enough, then an infrared meter, or infrared scope, can be used to identify areas of heating. Also, as another technique, a tracking generator with a spectrum analyzer can be used.)

I was the first (and only) engineer at my stations to monitor tower components in this manner.
The mathematics of a TDR is such that a supercomputer would have a difficult time with all the reflections in the time domain.
But the actual operation of a TDR is simple; And that is good, because a TDR is a very valuable instrument.
Not only was I chief operator for two stations, but I also was transmitter supervisor for all our transmitters. This TDR has enabled me to do a good job, and has paid for itself many times over.