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I Got The Air Conditioner Blues

Back in the day, when tube transmitters ruled the broadcast world, common practice was to have a big cooling fan moving outside air through the transmitter building connected to a thermostat.  Temperature swings of 30 to 40 degrees were common, however, the tube rigs could handle almost any temperature that didn’t melt plastic or freeze water.

Today’s solid state transmitters are not that rugged.  They like to have there rooms around 70 degrees +/- 10 degrees or so.  Not to mention the other computer controlled equipment commonly found at a transmitter site.  Things like air chain processors, STLs, remote controls, etc.  So, lots of air conditioning is the norm, and with lots of air conditioning comes lots of maintenance.

Air handler air filters need to be checked and replaced often.  Condenser coils seem to attract every type of flying debris on the planet and need to be cleaned once, possible twice per year depending on tree and weed species near the site.  Even with the preventative maintenance, occasionally things like this happen:

AC condenser frozen dryer and piping

AC condenser frozen dryer and piping

Of course, the entire cooling coil inside is frozen solid.

This condenser is low on refrigerant, causing icing problems.  It has a slow leak somewhere and is about to be replaced.  Other reasons for this happening are malfunctioning or non-existent low ambient kit on the condenser fan.  Sometimes less than knowledgeable persons will install a 5 ton unit designed to run throughout the year but not take into account the effect of moving below freezing air at high speed across the coils.  Insufficient air moving across the cooling coil will also cause this.  Insufficient air flow can be due to plugged air filters or clogged fan/blower blades.

This one is even better (same condenser unit):

AC condenser broken fan

AC condenser broken fan

The fan blade is sheared off and jammed into the condenser coil.  This happened during power transfer from generator power to commercial power.  Naturally, it was at 1 am in the morning after a pole mounted transformer had been replaced.  When the building transfered back to commercial power, I went outside to use the “bathroom” before my two hour drive back home.  I though I smelled something hot, you know that cooked paint/plastic smell, but couldn’t really track it down… the winds were kicking up and another thunderstorm was on the way.

The next afternoon, however, when the sun was up and the site was working on one air conditioner, the temperature alarm went off.  Upon arrival, I found the condenser breaker tripped, resetting it caused the building lights to dim.  The fan motor was shorted to case.  I would theorize the aluminum fan blade suffered from metal fatigue, likely because the blades were not balanced causing a vibration.  When the power transfer occurred, there was just the right combination of torque and centripetal force to cause the blade to rip, then lodge in the condenser coil.

The fan motor has replaced, but I think it is time to replace the whole condenser unit, which will be expensive.

AC&R Gauge set

AC&R Gauge set

I found having a set of gauges to check the head pressure and suction is a good diagnostic tool to quickly pinpoint problems with HVAC units.  This way, when the HVAC tech shows up, you can quickly point him in the right direction.

The breaker keeps tripping…

This is yet another addition of the “Burned up Sh*t” collection:

GE 30 Amp 3 pole breaker

GE 30 Amp 3 pole breaker

It is a breaker from a 5 ton AC compressor.  Back in the bad old days when I was the Director of Engineering for a 28 station group Headquartered in Harrisburg, PA, I received a phone call from one of the local engineers.  He stated that the studio AC unit compressor had burned out again and the breaker keeps tripping.  What did I think, asked he.  I thought perhaps he should dig a little deeper and determine why the breaker was tripping before throwing another AC compressor at it.  When are you coming to town again, he cheerfully inquired.

Okay, I get it.

I started by calling the HVAC company to inquire what had gone wrong with the compressors.  Winding shorted to case for both units was the answer received.  It being July and mighty hot out, the various worker bees in the studio where feeling inconvenienced by the sweat in their eyes and dripping on their work, etc.  I called the local manager and asked for a hotel room, I’d be up tomorrow.  Then I called the HVAC guy back and asked in to meet me at the studio tomorrow afternoon.

Upon arrival the next morning, I found the fifth floor studios to be hot, as reported.  I trip to the roof location proved to be hotter still.  I tested the voltages at the compressor unit with a DVM and everything looked good.  A trip down to the utility room found the electrical panel in reasonable shape.  Then the local engineering guy chimed in, “Oh yeah, I forgot to tell you, the breaker hums and gets hot when the compressor is on.”

It’s always that little bit of missing information…

I took the breaker out and sure enough, the fingers were all arched and nasty looking.

I replaced the breaker, the HVAC guy showed up, with a new compressor and the studios began to cool off around 3 pm.

Since then, I specify Square D QO bolt on breakers for new installations, especially for heavy loads like AC units, transmitters, and so on. They are a little more expensive, but in the light two AC compressors, the unscheduled trip out of town, and the grumbling staff, it is better to pay upfront for better equipment than to put up with preventable outages.

Cracked Battery Terminal

File under some new everyday. Yesterday, there was an area wide power outage in Woodstock, NY. The backup generator failed to start, however, WDST remained on the air until the UPS batteries ran out several hours later.  Then my cellphone rang.  Alas, yet another Sunday on the job.

Upon arrival, I found the power had just come back on, so the DJ (yes, there was a live person in the studio, on Sunday) was restarting the NextGen system and getting the station back on the air.  I restarted the rest of the servers, streaming computers and what not.  While I was there, I figured I might as well see why the generator didn’t run.

Pressing the start switch led to the “click, click, click, click…” which normally indicates the battery is dead.  Deciding that I should dig a little deeper, I got the volt meter out.  Battery voltage, no load 13.8 volts.  A normal reading.  Flick the starter switch and measure the battery voltage again, under load 13.7 volts.  Hmmmm, now that is not what I suspected.  If the battery were bad, the voltage should drop down under load.

Cracked Battery Terminal

Cracked Battery Terminal

I grabbed the negative cable and it came off in my hand.  Another one of those “ah ha!” moments.  Upon closer examination, the terminal connector is cracked in half.

Cracked Battery Terminal

Cracked Battery Terminal

I went to the local Ford dealership and bought a heavy duty truck battery cable.  Since the battery itself is six years old, I decided to bring it and have it checked, and sure enough, the battery was going bad too.  Rather than suffer through another power outage without generator, I went ahead and replaced the battery.

Why the terminal cracked in half in the first place, I don’t know.  Perhaps it was over tightened, or some type of manufacturing defect.

Care and feeding of Propane Fueled Generators

Broadcasters historically have tried to remain on the air during emergency events like major storms, earthquakes and other forces of nature.  Often times, commercial power is interrupted, and thus, the backup power generator is installed.  Propane powered generators for medium duty (powers up to 45 KW) are popular because of the decreased environmental hazards, availability and expense of fuel, ease of maintenance and repair.  This sized generator can run the critical loads of a studio facility or a transmitter site with TPO’s between 5 and 10 KW.

Katolight 45 KW generator w/outside housing

Katolight 45 KW generator w/outside housing

Most propane generators use a gasoline engine modified to use propane.  These generators can also use natural gas, however, because natural gas has slightly less energy, the generator’s service rating is reduced by about 10 percent.

Ford inline 6 cylinder engine

Ford inline 6 cylinder engine

The biggest error I consistently see with propane generators is improper fuel tank sizing.  It might seem just fine to plop a 500 gallon tank down next to a 45 KW generator and expect everything to be just fine.  500 Gallons may sound like a lot of fuel, but the more important consideration is tank vaporization, that is to say, how fast can the liquid propane can be removed from the tank for use.  Propane fuel companies should be able to sizing these things correctly, most of them have books and charts that tell what capacities and sizes are needed.  However, as a general trouble shoot guide, the following information is provided:

Generator manufactures will specify how many BTU per hour a generator will require under full load. If not, these are some conservative rules of thumb:

  • For every 1 KW of electrical generation, 2 horsepower of engine is needed*
  • Under full load, each horsepower will consume 10,000 BTU per hour*
  • Propane has 92,000 BTU per gallon
  • Propane weighs 4.2 pounds per gallon

*Note: These are not the figures you will find in your engineering handbooks, they are adjusted for generator winding and engine efficiency.

Propane Tank Vaporization Rates (Continuous BTU/hr vs volume at tank temperature):

Size propane in a tank (assumes 1/3 full) Maximum continuous BTU/hr at degrees F
20° 40° 60° 70°
120 129,600 188,640 247,680 308,160 338,400
150 146,880 213,790 280,700 349,200 383,520
250 253,800 369,400 485,000 603,480 662,700
325 321,300 467,670 614,000 763,900 838,900
500 396,270 567,700 757,300 942,240 1,034,700
1000 708,480 1,031,230 1,353,980 1,684,600 1,849,900
1450 816,120 1,253,400 1,645,690 2,047,550 2,248,480

Note: Tank vaporization depends on fuel level, tank temperature and withdrawal rate.  The above chart is a conservative generalization and represents a safe median value.

If a propane tank cannot vaporize fuel fast enough, the generator will begin to run lean, eventually overheat and shutdown. The vaporization rate depends on the tank temperature, which drops as fuel is withdrawn.  For the above cited 45 KW generator called to duty after a sever winter storm, the tank would need to vaporize: 45KW x 2 HP = 90 HP.  90 HP x 10,000 BTU/hr = 900,000 btu/hr.  A 500 gallon tank is too small for that size generator.

As the tank temperature drops a propane tank can develop frost on the outside of the tank, even on a hot summer day, which compounds the problem.

The correct size tank for a 45 KW generator is a 1000 gallons.  This can also be two five hundred gallon tanks connected in parallel via a high pressure line.

45 KW propane generator with two 500 gallon tanks

45 KW propane generator with two 500 gallon tanks

Also note, the generator’s radiator is facing the tanks so that when the unit is running, hot air is blowing on the tanks, warming them up.  This particular generator is about 25 years old, which is why it looks a little worn.  It still carries the load and mechanically is in sound condition.

Most propane fuel systems have two regulators; one high pressure regulator on the tank, which takes the variable tank pressure and steps it down to about 10 PSI, and the vaporizor which steps the pressure down to a few ounces per square inch (or inches water column) and adds air creating propane gas for the generator to burn.

High pressure propane tank regulator

High pressure propane tank regulator

It is important that the vaporizer be mounted above the snow line and that there is a little screen on the air intake, otherwise mud wasps will build a nest in the air intake and the next time the generator is required to run, it won’t start.

Low pressure propane regulator/vaporizer

Low pressure propane regulator/vaporizer

Fuel piping is also a concern, if the low pressure lines are not large enough to handle the required BTU, the generator will run lean, creating the same problems of an improperly sized tank.  Different piping has different capacities, see the following charts:

Propane steel pipe sizing diagram

Propane Schedule 40 steel pipe sizing diagram

Propane copper pipe sizing diagram

Propane copper-K pipe sizing diagram

Assumes pressure less than 1.5 PSI, one MBTU is equal to 1,000 BTU per hour.

Once the generator is installed, maintenance is required.  As a minimum:

  • Exercise engine bi weekly for 15 minutes. Propane generators do not need to run under load.
  • Check fuel, oil, and antifreeze levels monthly, more often if heavy use.
  • Change the oil, oil filter, air filter, check antifreeze freeze point, battery electrolyte specific gravity yearly
  • Change out belts and hoses as needed, pay close attention to the block heater hose, this is where leaks often develop
  • Clean out mice nests and droppings as needed

Mice love generators.

Tower Safety Equipment

The tower climbing video that has gone near viral pointed out a few things.  Climbing towers is dangerous business, best left to those who are trained for it and have the insurance.

It is true that tower climbing contractors have the responsibility to protect their own workers while working on a clients tower.  That does not completely absolve the tower owner from liability.  The it is incumbent on the tower owner to provide a safe structure to climb.  This can mean the mechanical integrity of the tower, reduction of transmitter power while workers are in high RF energy fields, and providing the proper permanently attached safety equipment on the tower itself;  Climbing ladders, ladder safety cages, rungs, elevators, and fall arresting gear.

In that tower video post, I mentioned something called a safety climb.  That is a cable, usually 3/8 inch stainless steel aircraft cable, attached, about eight inches from the climbing surface like this:

Western Electric 200 foot tower with retro fitted safety climb[

Western Electric 200 foot tower with retro fitted safety climb

The tower itself was built in 1959 and did not have this equipment when new.  This was a retro fit kit, installed in 2003, I believe.

The tower climber wears a harness with a special karabiner attached to the front and waist level.  When climbing this ladder, the karabiner slides up the cable.  If he were to fall, the karabiner has an auto locking or braking mechanism that would stop his fall.

Tower safety climb

Tower safety climb, attached to climbing ladder

Many tower climbers, especially those that have been in the business for a while, do not like these things.  When climbing, especially if one has long legs, the tendency is to bump your knees on the bottom of the next ladder rung.  This is because the belt holds the climber’s waist in making it difficult to get the rear end out, away from the ladder the way most people like to climb.  The alternative is to climb with the knees spread apart, like a frog, which is hard on the hamstrings and quite literally, a pain in the ass.  However, if a tower is so equipped, it must be used.

I have, wherever possible, retro fitted towers with these devices.  Of course, all new towers come equipped with them. In some situations, it is not possible to retro fit towers with safety climbs, either because there is no attachment point at the top of the tower that meets the OHSA spec, there is not a climbing ladder, or it would affect the tower tuning, as in an AM tower or near a TV or FM antenna.

Hundreds of gallons of ink have been spilled by Los Federals in OHSA regulations 29 CFR 1926 and 29 CFR 1910.268(g) regarding fall protection and fall protection equipment for telecommunications workers.  In this litigious world we live in, tower owners and or their on site representatives should know these rules and make sure they are followed.

The Problem with the Phone Company

It they don’t care all that much about traditional phone service anymore.  Through attrition, they have reduced their tech work force to about half what it was 15 years ago.  All of the infrastructure; over head cables, buried cables, office frames, switching equipment, is getting old.  Some of the cabling around here, both buried and overhead,  is the original stuff, installed 100 years ago.  Because it is expensive to replace, they don’t want to change it out, opting to simply limp along, swapping out pairs when a line or circuit goes dead.

I will be surprised if the traditional wired telephone network still exists in ten years.  Think about it, ten years ago were were just heaving a collective sign of relief that Y2K turned out to be nothing, remember that?

For the local phone giant, offering 3 in one (telephone service, internet service and cable TV) is more appealing than servicing their existing accounts, including HICAP (high capacity) data circuits like T-1, BRI&PRI ISDN, etc.  Much less so for a POTS line, which, good luck if you really need it fixed right away, we’ll be over when we get to it, just keep your paints on mister.

I’ve written about this before. A particular station for my former employer uses a T-1 circuit to relay the program from the studio to the transmitter site.  This is fairly common in larger metropolitan areas where 950 Mhz STL frequencies are not available, nor is line of site between the studio and transmitter site obtainable.

Back in 2002, when the company was in the process of aquiring said station, I recommended a 950 Mhz STL.  There was an existing STL license, fully coordinated, that came with the main station license.  Only the equipment was needed.  No, I was told by the CFO, we will do a T-1, thank you very much.  I argued my point, saying that putting our radio station exclusively in the hands of the phone company was a bad idea.  We would have problems with outages and service.  No, said the CFO, this is New York, all the radio stations do that.  Not exactly, New York is about 15 miles SOUTH of here, this is Westchester, the cables are old, a lot of them are overhead, which exposes them to lightning, vehicle damage, water, etc.  There will be service issues if we rely solely on a T-1.

No, he said, “We are using a T-1 and that is final.”  I hate to say I told you so, but… Let us examine the history between then and now:

Date of outage Date of restoration Total days
April 5, 2004 April 9, 2004 4
September 8, 2006 September 10, 2006 2
May 2, 2007 May 5, 2007 3
August 27, 2009 September 4, 2009 10
September 5, 2010 September 15, 2010 10

Fortunately, I wrote all this down in the transmitter site log.  I was able to check it yesterday, when I went to restore the station to normal operation after the latest T-1 failure.

During those periods, we have used BRI-ISDN, which is okay but it was carried the same phone cable.  It is likely to go down if there is a major cable interruption.  We have installed a second T-1 circuit, which fails when the other T-1 circuit fails.  We have used 3G wireless sprint card and streamed audio from the internet.  That didn’t sound great, but we did clear inventory.  We have moved one of the AudioVault servers to the transmitter site, and updated it once a day via shoe leather network, that sounded great, but it was difficult to do.  We have borrowed an ethernet connection from another tower site tenant onsite and streamed internet audio via wired connection, which sounds pretty good.

Still, the best thing to do would be to establish our own STL path to the transmitter and get rid of the T-1 lines.

The Problem with the Phone Company is they are not all that interested in simple copper circuits anymore.  Now, there is something called FiOS, which, it would appear is a much better profit center than ordinary copper circuits.

Rebuilt tubes

As broadcasters, we don’t really hear that much about ceramic power vacuum tubes these days, as more and more broadcast transmitters migrate to solid state devices.  Once upon a time, however, power tubes where the engine that drove the entire operation.  Tubes had to be budgeted for, stocked, rotated and replaced on a regular schedule.  Some of those dern things were expensive too.

Take the 4CX35,000A which was used in the Harris MW50 transmitters.  The transmitter used two of these tubes, one in the RF section and one it the modulator.  As I recall, new tubes cost somewhere north of $8,000.00 each from EIMAC.  Plus, in the A models there were two 4CX1500A driver tubes.  All of which could add up to an expensive maintenance cost every two years or so.

The next best option was to buy rebuilt tubes.  Rebuilt tubes were about half the cost of brand new ones.  Some people complain that rebuilds don’t last as long, or only last half as long as the new tubes.  I never found that to be the case.  I often found other factors effected tube life far greater, such as filament voltage management, cooling and by extension, cleanliness.

I can say I never had a warranty issue with ECONCO tubes.  I cannot say that about EIMAC, as during the late 90’s and early 00’s (or whatever you call that decade) I had several brand new 4CX3500 tubes that were bad right out of the box.  These days, ECONCO and EIMAC are both owned by CPI.

I spoke with John Canevari from ECONCO who had a lot of information.  For example, as the tube ages, the filament gets more flexible, not less.  Most ceramic power tubes use a carbonized tungsten filament containing some small amount of thorium.  As the tube ages, the filament can no longer boil off enough electrons and the emission begins to drop off.  That is the normal end of life for a power tube.  Occasionally, some catastrophic failure will occur.

There are many steps in the rebuilding process:

  1. Dud is received from the field, the serial number is recorded and the tube is tested in.
  2. The tube is prepped by sand blasting the sealing rings
  3. It is opened
  4. Filament is replaced.  In 60-70% of the cases, the grid is replaced.  In those tubes that have a screen assembly, 20-60% of those will be replaced.
  5. Interior of the tube is cleaned
  6. Tube is resealed and tested for leaks with a gas spectrometer
  7. Tube is placed on the vacuum machine.  Tubes are evacuated hot, smaller tubes take 12 to 24 hours, very large tubes can take up to one week.
  8. The tube is nipped off of the vacuum while still hot.  When the tube is fully cooled the vacuum scale is normally around 10-12
  9. Exterior of tube is cleaned and replated.  Silver for tubes that are socketed and Nickel for tubes that have leads.
  10. Tube is retested to manufacture’s original specification or greater.

After that, the tube is sent back to its owner or returned to stock.  John mentioned that they are very proud of there vacuum tube processing machines, so I asked if he could send along a picture.  They certainly look impressive to me, too:

vacuum tube processing machine

Vacuum tube processing machine, photo courtesy of ECONCO

Not exactly sure which tube type these are, but they sure to look like 4CX15,000:

vacuum pump on rebuilt ceramic power tubes

Vacuum pump working on rebuilt ceramic power tubes, photo courtesy ECONCO

Econco has been in business since 1968 and rebuilds about 600-1,000 tubes per month.  In the past, broadcasters used most of the larger tube types.  However, with the majority of broadcast transmitters shifting to solid state, other markets have opened up such as industrial heating, military, research and medical equipment.

Copper theft and how to avoid it

One of the unfortunate signs of the times is increased theft of valuable materials. Copper, while not as expensive as it once was, still fetches a fair amount at the scrap dealer. One local telephone company has been having a difficult time keeping their aerial cables intact in certain areas. For radio stations, the situation is compounded by remote transmitter sites with lots of copper transmission lines and buried ground radials around AM towers.  Reduced staffing levels also means that the weekly trip to the transmitter site is now every two weeks or perhaps once a month or even less.

Site that are not visited or monitored very often are prime targets for copper theft.  Forget asking the local constabulary to patrol more often, the few times I tried that I was met with a blank stare.

A few common sense type things that I have learned over the years may keep your site intact:

  1. Keep  up appearances.  A neglected transmitter site is more likely to attract the wrong type of attention from the wrong type of people.  Clean up any rubbish, dead equipment, keep the weeds and trees cut down, etc.  If a site looks well tended and often visited, a thief may think twice about lifting valuable metals.
  2. Along with #1, keep things buttoned up.  Secure all transmission lines to ice bridges, remove any dead lines, etc.  If there are ground radials poking out bury them, same with ground screens, copper strap, etc.  Out of sight, out of mind, leaving this stuff exposed is asking for somebody to come along and give a tug.
  3. Fences and locks.  Towers are required to be fenced and locked to prevent electric shock hazard.  It is also a good idea to fence the building, generator and fuel tank if possible.
  4. Post all sorts of warning signs, RF warning, high voltage, no trespassing, under video surveillance, pretty much anything to deter trespassing and vandalism.
  5. Add video cameras with a video recording device since most theft occurs during non-working hours.  Last year, the company I used to work for traded a video surveillance system for the studio location.
  6. Compensate a neighbor to keep an eye on the place and call you if they see any suspicious activity.  It doesn’t even have to be money, I once worked out a deal with a neighbor for some T-shirts and CD’s.   That was the best alarm system we ever had.

In the long run, keeping all the copper parts where they belong is a great way to avoid those annoying “the station is off the air” phone calls not to mention the expense of replacing damaged transmission and ground systems.

AM transmitter site maintenance check list

As promised, here is the AM transmitter site maintenance check list.  This is for a generic directional AM station with a backup transmitter, generator and an RF STL.

Broadcast Electronics AM6A transmitter

Broadcast Electronics AM6A transmitter

Usual disclaimers apply.

AM site Maintenance checklist

Weekly Maintenance:

A.  Visit site, Check following:

  1. Check critical transmitter values against last logged value
  2. Check forward/reflected power on main transmitter
  3. Check and reset any overloads
  4. Check signal strength on STL against last logged value
  5. Check generator fuel level
  6. General check of building, look in all rooms, inspect for damage from vandalism, Leaking roofs, obvious signs of trouble, take steps to correct.

Monthly Maintenance:

B.  Visit site, Check following:

  1. Do a full multi-meter log, (includes tower phase angles, loop currents), run backup transmitter into dummy load.
  2. Start and run generator for 5 minutes, check block heater, hoses, belts, oil and antifreeze levels
  3. Calibrate remote control meters with transmitter meters, log it*
  4. Check all tower fences for integrity and locked gates*
  5. Complete Items 3, 4 and 5 under weekly maintenance.

Quarterly Maintenance:

C.  Visit site, Check following:

  1. Complete 1 through 5 under monthly maintenance.
  2. Check all air filters, clean or replace as needed.
  3. Check frequencies of all transmitters, STL receiver, and log.
  4. Complete quarterly tower lighting and painting inspection*

Bi-yearly Maintenance:

D.  Visit site, Check Following:

  1. Complete 1 through 5 under quarterly maintenance.
  2. Conduct monitor point readings for all directional antenna patterns*
  3. Check base current readings for day/night towers.  Ratio.*
  4. Clean backup transmitter
  5. Place backup transmitter on air and clean main transmitter.

Yearly Maintenance:

E.  Check all licenses and authorizations for accuracy. Make sure that all renewal cards etc are in public file and are posted at control point.*

F.  Visit site, Check following

  1. Complete 1 through 5 under Bi-yearly maintenance
  2. Equipment performance measurements (NRSC, Harmonics, frequency)*
  3. Complete service of generator
  4. Complete Inspection of towers, check for vertical and plumb, check guy wire tensions, retension as needed.
  5. Check property for anything out of the ordinary
  6. Repair driveway as needed

General maintenance that is completed on an as needed basis

  1. Re-fill fuel generator fuel tank when drops below 50 percent
  2. Empty trash, sweep floors, dust.
  3. Cut/remove vegetation inside tower fences, spray herbicide as needed
  4. Water proof tower fences every 2 years
  5. Paint exterior of building
  6. Replace tower lights*
  7. Paint towers*

*These are FCC inspection items, pay close attention if you do not want a fine.

That is it, a .pdf version of this file can be downloaded here.

Working with Tower Companies

Almost all radio stations use a tower of some sort to support their transmitting antennas.  These towers need maintenance from time to time and only qualified people should perform maintenance on towers.  Hence, the tower company is formed.

405 foot guyed tower with ERI FM antennas

405 foot guyed tower with ERI FM antennas

Over my years of experience, I have dealt with many different tower companies, from one man operations to big corporations that have multiple crews out in the field on any given day.  I have discovered that not all tower companies are created equal.  Not only do tower climbers need to be in good physical shape and be trained correctly in all tower climbing safety procedures,  they also need to be good mechanics so they can actually repair things on the tower.   Climbing a 470 foot tower to repair a strobe light is all well and good.  Once the climber gets to the strobe light, he needs to be able to disassemble it without dropping parts or breaking things, trouble shoot if needed, install new parts and re-assemble the unit, again without dropping or breaking anything.

Applying a RF connectors, installing a FM antenna or STL antenna, repairing light fixtures or conduit all require some amount of manual dexterity and concentration.  Assembling high powered antenna requires close attention to detail.  Any pinched O rings, cross threaded bolts, bent bullets and the antenna will have problems, likely at the worst possible time.

The sign of a bad tower company is if it’s climbers cannot carry out those tasks with one or at most two climbs.  I have a situation on a tower where our FM station is a tenant.  The tower has a strobe light failure near the top of the tower where our FM antenna is located.  They have climbed the tower no less than four times to repair this, and it is still not fixed yet.  Each time they climb, the station has  to reduce power to protect the tower climbers from excessive RF exposure.  Each climb it takes them several hours longer than anticipated to finish their work.

A good rule of thumb, If the defective part cannot fixed in the first two climbs, then the entire strobe unit should be replaced on the third climb.  Even though the strobe units are expensive, by the time they get done paying for all this tower work, they could have bought two new strobes.  Today will be the fifth climb and there is no guarantee that it will be fixed.

I advised the tower owner that they should be looking around for another tower company because these guys aren’t exactly setting the world on fire.

Axiom


A pessimist sees the glass as half empty. An optimist sees the glass as half full. The engineer sees the glass as twice the size it needs to be.

Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
~1st amendment to the United States Constitution

Any society that would give up a little liberty to gain a little security will deserve neither and lose both.
~Benjamin Franklin

The individual has always had to struggle to keep from being overwhelmed by the tribe. To be your own man is hard business. If you try it, you will be lonely often, and sometimes frightened. But no price is too high to pay for the privilege of owning yourself.
~Rudyard Kipling

Everyone has the right to freedom of opinion and expression; this right includes the freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers
~Universal Declaration Of Human Rights, Article 19

...radio was discovered, and not invented, and that these frequencies and principles were always in existence long before man was aware of them. Therefore, no one owns them. They are there as free as sunlight, which is a higher frequency form of the same energy.
~Alan Weiner

Free counters!