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The Shukhov Tower

A very interesting bit of broadcasting history in Moscow may disappear forever.  Designed and built by Vladimir Grigoryevich Shukhov, the Shukhov Tower was completed in 1922.  Since that time it has served as a AM broadcasting and later and FM broadcasting tower.  In the picture, one can see what looks like a massive FM panel antenna at the top.  According to this website: www.shukhov.org, the tower is in very poor shape and is slated to be demolished.

The tower itself is described as 160 Meters (525 feet) tall, hyperboloid steel lattice structure. The design is unique in that it is very strong, yet uses approximately 60-70 percent less steel than a comparable four legged structure like the Eiffel tower.  An amazing feat of engineering for its day, when everything was calculated and drawn by hand.

Shukhov Tower, Moscow, FSR

Shukhov Tower, Moscow, FSR.

The antenna is a little hard to discern, however, it looks like a horizontally polarized six or eight around 4 bay FM antenna. Could also be low band VHF TV.

Shukhov Tower antenna

Shukhov Tower antenna. Courtesy Wikipedia

Unfortunately, time is running out and little or nothing is being done to protect the steel structure from the elements. The last paint job was more than twenty years ago. The land it currently occupies has some value, and there is talk of putting up a high rise development in its place.

Article from the New York Times; An engineering landmark faces demolition in Moscow.

There are lots of videos on youtube and pictures from the wikipedia article.  It is an interesting bit of history, if it can be saved it will be a very close run thing.

North Adams Tower Collapse

High winds seem to be the culprit in the collapse of two towers in North Adams. According to the Motorola system technicians, it happened at about 12:30 am Sunday morning, which is when all their link loss alarms started going off.  The larger, self supporting tower broke from it’s mounting plate and tipped over into the smaller guyed tower next to it. Effected are WUPE-FM and W226AW (WFCR New England Public Radio) as well as NEPR new station WNNI which has not officially signed on.

Cellular service for ATT, Verizon and Sprint/NEXTEL were all knocked off line as well internet services and E911 dispatch.  Those services are coming back on line, with temporary modular cell units en route. News report from WWLP channel 22, Springfield, MA:

Here are some pictures:

North Adams Cell Tower

North Adams Cell Tower

WUPE-FM antenna on the ground

WUPE-FM antenna on the ground

WUPE-FM antenna

WUPE-FM antenna

WUPE-FM STL dish

WUPE-FM STL dish

Base of WUPE-FM (formerly WMNB) tower

Base of WUPE-FM (formerly WMNB) tower

WNNI antenna

WNNI antenna

WUPE-FM WNNI and W266AW transmitter building

WUPE-FM, WNNI, and W266AW transmitter building

North Adams Cell Tower

North Adams Cell Tower

North Adams Cell Tower

North Adams Cell Tower

North Adams Cell Tower

North Adams Cell Tower

North Adams Cell Tower

North Adams Cell Tower

Tower base mounting plate, apparent failure point

Tower base mounting plate, apparent failure point

Tower base mounting plate

Tower base mounting plate

Tower Base Mounting Plate

Tower Base Mounting Plate

For pictures of the towers during happier times, refer to this post: Filtering for co-located FM transmitters.

Restoration work is underway with WUPE-FM expected to return to air at low power by Monday afternoon.

Update:

WUPE-FM was returned to air at low power by about 1pm on Monday 3/31.  We took an unused Shively 6812 antenna that was tuned to 94.1 MHz and retuned it to 100.1 by cutting 1/4 inch pieces from the end of the elements until it was on frequency.  It took a bit of doing, but with a network analyzer, we were able to get it to 1.2:1 SWR with symmetrical sidebands.  Running 600 watts, it covers the city of license and then some.

WUPE-FM temporary antenna

WUPE-FM temporary antenna, Shively 6812

The STL antenna is a survey antenna mounted on the side of the building. In this configuration, with the leaves off of the trees, we are getting about 250 uV signal, which is pretty good.

WUPE-FM temporary STL antenna

WUPE-FM temporary STL antenna

The site is now crawling with insurance investigators, cell site technicians, North Adams fire department, Berkshire County Sheriff’s officers, tower workers, etc.  After we finished this work, we cleared out to make more room for everybody else.  Estimated restore time for W266AW is Wednesday 4/2.

Planning for the replacement tower is already in progress, I’d expect it to happen fairly quickly. The next step for the broadcasters is to put up a 70 foot utility pole and get a full powered antenna for WUPE. This should happen in the next two weeks or so. That will serve as the temporary facility until the new tower is constructed.

The NASH: WNSH, Newark, NJ

Lately, I have been working at a site in West Orange, NJ connecting various parts and pieces and thought that this was interesting:

WNSH 94.7 MHz, Newark, NJ main antenna (top)

WNSH 94.7 MHz, Newark, NJ main antenna (top)

That is the main antenna for WNSH, 94.7 MHz Newark, NJ, aka “Nash-FM.”  Below that is the backup antenna for WEPN-FM (98.7 MHz), WQHT (97.1 MHz) and WFAN-FM (101.9 MHz).  More on those stations later.

WFME studio building

WFME studio building

This is the WFME studios, located off of NJ Route 10.  It is kind of hard to see the call letters behind all those trees and whatnot.  There is an older picture from 1999 floating around, which shows the studio building in better condition.  This is a better angle:

WFME studio

WFME studio

I believe WFME is still originating its programming here, now being broadcast on WFME 106.3 MHz, Mount Kisco.  I had to use the facilities there, the interior is like a way back 80′s time machine, which is kind of cool.  If I owned a radio station, I would go for the 70′s office decor; dark wood paneling, shag carpets, bright blue bathroom tile and avocado green appliances, but hey, that’s just me.

WNSH backup antenna, WFME-TV antenna

WNSH backup antenna, WFME-TV antenna

This is the WNSH backup antenna, mounted on top of a UHF slot antenna for WFME-TV.  There is an LP TV antenna mounted there also, but I don’ t know who it belongs to.  Overall, it is an interesting transmitter site on “First Mountain” in West Orange, NJ.  Also located here, WFMU-FM, an old ATT microwave site, now owned by American Tower and several cell carriers.   In other words, it is just like most other mountain top transmitter sites, except there is a shopping plaza across the street.

I gave a listen to the NASH while driving there.  For where it is, it seems to have a pretty good coverage area.  As for the music, well, I am not sure how a Manhattenite will relate to Tracy Byrd’s “I’m from the Country” wherein:

Everybody knows everybody, everybody calls you friend
You don’t need an invitation, kick off your shoes come on in
Yeah, we know how to work and we know how to play
We’re from the country and we like it that way

Being from upstate NY, I get it.  Perhaps the Manhattan salary man will too.  There are no DJ’s on air quite yet, just music, some commercials and a few “Nash-FM” liners that sound slightly distorted.

Zonecasting; the Technical Details

I saw this a item many weeks ago, however, had not had time to look at it until now.  Geo Broadcasting Solutions has filed Petition for Rule Making (RM-11659) based on a system divides the coverage area of major stations into smaller zones allowing for ad targeting of specific audiences.  They have coined the term “Zone Casting” to describe the scheme. It is covered by two US issued patents filed by Lazer Spots, LLC: 20120014370 and 20110065377.  After a look at these two patents, it seems there are three possible ways to accomplish this Zone Casting Scheme:

  1. In the first described method, the main transmitter is broadcasting area wide and all the zone transmitters are muted.  An inaudible signal is transmitted to all units, the main transmitter is then muted and the zone transmitters turn on and transmit localized content.  After the local information is transmitted, the zone transmitters mute and the main transmitter resumes broadcasting.
  2. In the second described method, the main transmitter and the zone transmitters are broadcasting area wide information.  The main transmitter ceases broadcasting area wide information and the zone transmitters begin broadcasting localized information.  At the end of the localized information the main transmitter and zone transmitters transmit area wide information.
  3. In the third describe method, the main transmitter and zone transmitters are broadcasting wide area information with “capture ratio pattern.”  The main transmitter initiates an alteration, temporarily becoming a zone transmitter.  The zone transmitters then transmit localized content.  After the localized content, the main transmitter becomes a main transmitter again.

All of the transmitters are linked to the studio via digital STL systems, content for the zone transmitters is distributed via IP network.  The transmitter frequencies are synced with GPS, similar to FM on channel booster stations.  Method number three includes possibly switching the transmitter output to a lower gain and or lower height antenna.

Zone Broadcasting Conceptual Diagram

Zone Broadcasting Conceptual Diagram

Of the three methods, the first system will result in the fewest interference issues.  No matter which method is used, there will be interference issues between the zone transmitters and or the main transmitter where the signal strengths are equal and the audio is 180 degrees out of phase.  These can be moved around slightly by adding delay to the audio signal, but they will always be present.  More about Same Frequency Networks (SFN) and Synchronized FM signals can be found here.  While the zone transmitters are transmitting dissimilar localized information, standard capture effect rules apply.

The system has had limited testing in Salt Lake City, Utah (KDUT) and Avon Park, Florida (WWOJ), which according to the filing and comments, went well.

Geo-Broadcasting is applying to conduct a full test with WRMF in Palm Beach, FL.  The expected installation will include up to 22 zone transmitters.

Conceptually, tightly targeted advertising is not a bad idea.  Advertisers like it because they perceive a better return for their dollar.  The cost of such a system is not insignificant. Transmitter site leases run $1-2K per month, leased data lines, equipment, installation work, equipment shelters, etc will likely run several hundred thousand dollars or more.

If it gets approved by the FCC, it will be interesting to see how it works and whether or not the system is financially justifiable.

 

North East Commerical Radio Antennas and Towers

NECRAT logo

NECRAT logo

Or NECRAT for those who have been around the internet for a while. Many, if not most of you will know Mike Fitzpatrick’s NECRAT website which features many pictures of radio transmitter sites around the country (not just the Northeast).

Even before I began blogging, I checked NECRAT often for interesting pictures of many different transmitter sites.

If you are one of the few who has not visited his site, go and check it out: http://www.necrat.us

PBS Frontline: Cell Tower Deaths

Interesting video (part 1 of 3) about the large numbers of Cell tower deaths in the last eight years:

Watch Cell Tower Deaths on PBS. See more from FRONTLINE.

There are two kinds of tower companies, those that have been around for a long time and do things right, and those that hire subcontractors who are minimally trained and take shortcuts. The reasons for this are the same and we hear them over and over again in all aspects of this business; budgetary constraints, time constraints and what, who me?

The rest of the videos can be found at PBS.org:  Frontline: Cell Tower Deaths

Written story from Propublica: In Race For Better Cell Service, Men who climb towers loose their lives.

Tower light malfunction

We were notified that the WFAS-AM tower lights were out, thus, it was time to investigate. This problem was easy to find. Upon removing the water proof cover on the tower light flasher box, I found this:

SSAC melted tower light flasher, damaged by lightning

melted SSAC B-KON tower light flasher, damaged by lightning

As soon as loosened the screws on the cover, I smelled the unmistakeable odor of burned electronics and plastic.   I disconnected the flasher and covered the photocell, which turned the side markers on.  Of course, the top flashing beacon was dark, therefore, it was time to report the outage to the FAA.  The nation wide number to report tower light outages is (877) 487-6867.  That number is for an automated system, however, eventually it leads to a live person.  Since the new reporting system was established, the only required information is the tower ASRN.  From that information, the operator will access a data base and have all the required information to issue a NOTAM.  In the past, many questions were usually asked; what is the nearest airport, how far away is the airport, how tall is the obstruction, what is the position, etc.  Therefore, things have become slightly easier than before.

Once the outage is reported and a NOTAM is issued, the tower owner generally has fifteen days to correct the problem.

So, you call this work?

A trip to the WSPK transmitter site on a pleasant day, or, one could say, another day at the “office.”  Tower painting season is here, I’ll post some more about that later.  This is a nice set of pictures from the top of Mt. Beacon, in Beacon, NY.

Hudson Valley looking north from Mt. Beacon

Hudson Valley looking north from Mt. Beacon

South Mount  Beacon with the old fire tower:

Mount Beacon looking south at the old fire tower

Mount Beacon looking south at the old fire tower

Tower farm; two TV stations, Media Flow, one radio station, three translators, several cell carriers, one paging company, some government two way gear, and a few microwave relays.  The 320 foot guyed tower in the center holds the main (top) and backup (bottom) antennas for WSPK:

Mount Beacon Tower Farm

Mount Beacon Tower Farm

Tower climbers ascending a 320 foot tower.  This picture (and all the others as well) was taken with my HTC smartphone camera, proving the old adage, sometimes it is better to be lucky than good:

Tower workers on 320 foot guyed tower

Tower workers on 320 foot guyed tower

View from the ATC site at the very top of North Mount Beacon of the tower workers painting the top of the tower:

Tower workers painting torque arms on 320 foot guyed tower

Tower workers painting torque arms on 320 foot guyed tower

Another view from the ground:

Tower workers on Mt Beacon tower

Tower workers on Mt Beacon tower

All in all, not a bad day.

WSPK antenna replacement, part I

WSPK is located on North Mt. Beacon, which is the highest point for miles around. It has a fantastic signal. The site is a little difficult to get to, however, especially in the winter.  In previous years, the road has been impassable four months out of the year.  Some engineers have hired a helicopter to get up there when the snow is deep.  For that reason, it is important to keep the equipment in good shape.

WSPK Shively 6810 antenna with damaged top radome

WSPK Shively 6810 antenna with damaged top radome

After last February’s snow/rain/ice storm, it was noted that the top antenna radome was missing it’s top.  A tower climber was sent up to look at it and it was also discovered that the top bay was bent down and the element was almost cracked in half.  A result of falling ice, likely from the big periscope microwave reflector (passive reflector) mounted above it.

WSPK tower

WSPK tower

The periscope reflectors went out of service in 2007, but the tower owner did not want to pay to take them down, thus a problem was not being solved.   It was decided to replace the 25 year old Shively 6810 antenna with a new one, during which work, the radio station would pay to remove the reflectors from the tower.  In exchange for that work, the radio station would then be able to repair and remount the old Shively antenna below the new one, thus having a backup antenna.  Problem solved, except for, you know:  The actual work.

The tower and the periscope microwave system was installed in 1966, operated on 12 GHz and was used by the Archdiocese of New York to relay their educational television programming from their Yonkers headquarters to the various schools in the Hudson Valley.  Sometime around 1975 or so, the FCC mandated that periscope microwave systems could no longer be used due to all the side lobes and interference issues they caused.  They were to be taken out of service as soon as possible.  The Catholic Church, being a multi millennial organization figured “as soon as possible” meant within the next fifty years or so.  Anyway, somebody else needed that frequency, therefore in 2007, they bought the Archdiocese a new digital microwave system.

The problem with the reflectors; they are big.  They are also heavy, and present a huge wind area.  They are also 300 feet up in the air.

WSPK tower periscope reflectors seen from ground level

WSPK tower periscope reflectors seen from ground level

Finding a day with lite winds on top of Mount Beacon can be a problem.  Luckily, the weather was with us.  Still, it took a while to get this work moving along.  The other consideration is RFR and tower climber’s safety.  There are two digital TV stations, WSPK, several cell carriers, something called “Media Flow,” and a bunch of two way radio repeaters.  The main concern was WSPK, the DTV’s and Media Flow since the top of this tower is right in the aperture of those antennas.  All either went way down in power or off the air while this work was on going.

Rigging a gin pole and getting it to the top of the tower was a chore.  The gin pole needed to be threaded through those torque arms like a needle.

Gin Pole

Gin pole

The tower riggers truck had two winches, one a basic 120 volt capstan, the other a hydraulic winch in the bed of the truck with 1/2 inch steel cable.

Tower rigger's truck

Tower rigger's truck

The bolts holding the reflectors in place had to be cut with a saw, you can see the tower climber working on the left hand reflector, gives you an idea of size.  If this reflector were to fall off the tower, chances are good the major damage and or injuries would result on the ground.  Proceed with extreme caution.

Cutting bracket mounting bolt on periscope reflector

Cutting bracket mounting bolt on periscope reflector

Carefully lowering reflector past Shively 6810 FM antenna and Scala PR-950U microwave antenna.  During this phase, the tower climbers had to push the reflector out away from those obstacles with their legs.  You can see the gin pole at the top of the tower.

lowering periscope reflector

Lowering Periscope reflector

Another view:

Lowering reflector

Lowering reflector

Another view:

Lowering reflector

Lowering reflector

Almost down to the ground.  This measured 15 by 10 feet and ended up weighing 830 pounds.

Reflector almost to the ground

Reflector almost to the ground

One down, one to go.  I can’t believe those gigantic things were at the top of this tower, on the top of this mountain for 43 years and the tower is still standing.  This is going to change the appearance of the mountain top from down below.  For years, it looked like a pair of mickey mouse ears, now it will only look like a tower.  I wonder what the environmentalists will think.

I will make a second post with the antenna pictures as this one is getting a little long.

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.

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