As the LBA Antenna Turns

As the most experienced firm offering AM detuning services, LBA gets some complicated requests. LBA’s professionals are mostly unsung when they accomplish these missions.

Kathryn Tesh and the LBA team recently set straight a cellular tower detuning project in the Pacific Northwest, saving the cellular customer considerable money in the process. So it was a bit of a Holiday gift to receive kudos from both the station consulting engineer and the wireless carrier project manager. Here’s what they said (slightly edited for privacy):

From the consulting engineer:

“The ownership of K*** has asked me to respond to the engineering study performed to determine re-radiation potential.

I see no problems and I appreciate this careful work.  We have a history of concern expressed by the (on channel) station in Seattle and consequently have been careful to maintain our night-time directional.

LBA has done excellent, careful engineering.  Please proceed.”

From the client carrier manager:

“Thanks I have the reports and believe this closes out the projects.  I hope you have already invoiced for everything and I have approved what has come my way.

I agree with the K*** engineer.  These projects were somewhat complicated with the three sites and our early construction of one of the towers.  I am very pleased with how LBA handled the whole thing. My compliments to yourself, Mike and the LBA team.”

And, as we write this, here’s a thank you just in on another project!

A carrier construction contractor needed really fast response involving the dispatch of an LBA engineer to a remote California location over Christmas week. Unfortunately, an LBA competitor had walked away from the project, leaving the contractor stranded with a deadline. The LBA report was on the client’s desk this morning!

Here’s what the Program Director said to Kathryn:

“Excellent work.

I have reviewed the report and I appreciate the completed analysis.

I may have questions later today but for now this report as delivered is much appreciated.”

We very much appreciate the customer feedback. LBA has been performing consulting services since 1963, always with customer satisfaction as the #1 priority. Please contact Mike Britner to enjoy LBA superior professional services in AM and EME wireless compliance services.

Lawrence Behr Associates cleared the path for a new electricity transmission line in New York that that could not be energized until interference problems with a Rensselaer, N.Y., AM radio station were resolved to the satisfaction of the New York Public Utility Commission.

After extensive onsite and computer analyses, LBA engineers determined that 8 of 33 tall power towers on this line in the proximate area of station WGDJ-AM would disrupt the stations licensed coverage pattern and require installation of detuning systems.

Utility constructors installing AM detuning system on East Greenbush 345 KV transmission tower.

The transmission towers carry a 345 kV electrical power line from a 635-megawatt natural gas fired power plant constructed in Rensselaer by Empire Generation Co. LLC. The distribution system has 70 towers in all, the last of which were erected last summer. The question was how many of them near East Greenbush, N.Y., would cause signal interference with broadcasts of the AM station. The interference would have created a violation of FCC rules governing the integrity of broadcast signals.

Transmission towers often are a height that makes for efficient radiation of medium wave AM signals. The broadcast AM signal is intercepted from the environment by the power tower and “reradiated”. This reradiated AM signal interferes with the designed coverage and interference of the AM broadcast antenna system. The Federal Communications Commission licenses AM station antenna systems to very tight tolerances, and only a few percent reradiated powerline signal can seriously impact the licensed pattern performance.

The proper evaluation and remediation of power line reradiation can be complex. The multiple transmission towers and the coupling between them through lightning shield wires can be a challenging analysis, but also spread the impact much more broadly than would a single tower. These interconnections form conductive loops which have vastly different electrical properties than single towers. Normally, a technique called “detuning” is applied, along with modifications of lightning shield wires. The recent practice of embedding fiber optic cable in these wires has made these mechanical modifications quite a bit more complicated.

To evaluate and resolve the New York problem, Lawrence Behr Associates was called in by CH2M Hill, an international consulting engineering firm based in Colorado. The eight disruptive transmission structures were subsequently identified through field measurements and software modeling. Their negative impacts were remediated by an AM protection detuning process, allowing the project to proceed. The offending structures were detuned using custom-engineered LBA Technology hardware along with modifications to the new power line. Modifications were carefully designed for safety and usability in conjunction with CH2M Hill and the owners, and implemented by LG Constructors. Necessarily, all detuning hardware was constructed, installed, and documented to rigorous utility standards.

LBA engineer Mike Hayden adjusting AM detuning system control box.

LBA has employed a similar process hundreds of times to detune cellular industry towers with AM radio interference problems of their own. While technological applications vary in each case, they are rooted in the same family of engineered solutions. This was an important design consideration, as renting transmission tower space to wireless carriers is an important revenue source for utilities. In the event the detuned towers were to be rented to a carrier to support their antennas, the AM dutuning documentation would also support the carrier’s FCC AM protection requirements.

Interactions between high voltage transmission systems and AM stations are expected to grow in future years. Thousands of miles of powerlines are planned to support the smart grid, wind turbine, and photovoltaic power generation. Many of these will pass near AM broadcast antennas. It is vitally important for utility planners to have proposed routes reviewed by an RF engineer, like Lawrence Behr Associates, early in that process. If lines can’t be rerouted, then detuning can be incorporated in the design process, at great savings over construction stage delays or modifications.

For more information, contact Mike Britner.

 
Installing SAMWAS-200 ATU

Ships sailing in waters near Guam have a new connection to shore. The island’s NAVTEX navigational telex broadcast system has been upgraded by replacing three conventional 300’ vertical towers with one small aperture SAMWAS antenna

The unique SAMWAS medium wave antenna system is a product of LBA Technology, a North Carolina telecommunications firm with over 40 years experience in antenna innovations. The company’s engineered solution for the Guam site is replicable at most other NAVTEX locations worldwide.

NAVTEX Stations World Wide

The coastal telex broadcast system called NAVTEX is a vital link for commercial and military ships operating within 400 miles of a coastline. NAVTEX is a maritime safety system typically operated by navies, coast guards, or lighthouse authorities in coordination with the International Maritime Organization (IMO). The shore-to-ship signals are sent out at either 518 kHz or 490 kHz. 

For the US Navy transmission site on Guam, LBA Technology used a suite of subsystems called SAMWAS-200 that incorporates a grounded 199 foot electrically short transmission antenna rated at 2500 watts. Installed for LBA in the spring of 2009 by Guam contractor AIC International Construction, the antenna’s propagation of medium wave signals has proven effective and efficient, though its physical footprint is much smaller than the three-tower system it replaced.

The short height avoided the need for aviation safety lights and the associated installation and operating costs. The grounded tower reduces system vulnerability to lightning and reduces RF safety hazards.
 
The transmitter building is located fully 3,000 feet from the tower. As the dual frequency SAMWAS-200 Phantom-E™ remote control system can use a coaxial cable as its sole connection for both RF and control signals, an existing coaxial cable was utilized with no new trenching for electrical services. The Phantom-E™ system selects between 490 and 518 kHz frequency modes.

As there are no moving RF parts in the SAMWAS tuning unit, it is expected to function reliably for years with minimal maintenance. Because of the stability of the overall system, periodic retuning is not needed to accommodate changing environmental conditions.

Other SAMWAS antenna systems from 65 to 350 feet high are available to support DGPS, NAVTEX, and GMDSS medium wave transmissions. Dual NAVTEX frequency support and DGPS diplexing are options. Full turnkey projects with transmitters and message equipment are offered.

For tactical communication situations, LBA Technology offers medium wave transmission systems integrated into trucks or trailers, and smaller emergency units that can be assembled on site by hand.

New England radio station owner Bob Vinikoor looked past the momentary inconvenience of installing wireless carrier antennas on his AM radio towers and saw a steady stream of revenue. The same sight awaits almost any radio station owner willing to look into the matter.  

Lawrence Behr Associates can help. We make it possible to generate new revenue from old towers.

Vinikoor – the president of Koor Communications – listened to a proposal from a wireless carrier five years ago and soon thereafter his 200-foot-tall tower for WNTK-AM 1010 was earning him extra revenue. The tower now is home to 4 wireless carrier antennas. In all, three of four towers serving Vinikoor’s stable of radio stations in New Hampshire and Vermont are partnering with wireless companies.
 
To help Vinikoor reap more income from his existing facilities, Lawrence Behr Associates utilized a patented signal isolation device developed by LBA Technology engineers called CoLoCoil.

“I’ve never had a problem with the CoLoCoils,” Vinikoor says, referring to the original installation and several others that followed on his towers. “I would certainly recommend colocation of wireless and other carriers. It is painless.”

Vinikoor believes many AM radio station owners haven’t offered their towers for collocation because they have never been asked. Why? Wireless carries aren’t aware of their towers. Vinikoor recommends that owners have their towers listed – it’s free – by the Federal Aviation Administration so wireless companies know of their existence.

Vinikoor charges different rates. The higher on a tower an antenna is placed, the greater the premium charged. Vinikoor’s wireless partners pay from $1,600 to $2,400 a month to collocate on his structures.

“There is a little down time during the construction phase, some lost broadcast time,” he says, “but the revenue from the leases more than makes up for the lost time up front.”

Can wireless carriers and AM radio station towers partner? You betcha! There is a proven collocation engineering system that successfully weds wireless antennas and AM towers. In this blog, Lawrence Behr, founder and chief executive officer of LBA Group Inc., explains how it’s done.
 
Historically, the wireless industry has been warned to steer clear of AM radio stations. The towers were considered unsuitable by most wireless carriers (cellular, PCS, SMR) because of presumed grounding difficulties, interference and safety considerations.

Not today! We have developed new technologies to overcome these problems and efficiently integrate wireless and AM systems at reasonable costs.

Our technological approach to AM colocation is a proprietary system called CoLoSiteSM. This technology has been developed through the collaboration of two LBA Group companies with more than 35 years of experience in AM broadcast and wireless industries.  The system is based on patented hardware by LBA Technology, Inc. with engineering and integration systems implemented by Lawrence Behr Associates, Inc.
 
With CoLoSiteSM, collocation is practical for both single tower and multiple tower AM antenna systems. Using the system, wireless antenna and coaxial cable installations have virtually no effect on host AM towers and the AM signal has no effect on the wireless antenna.

Moreover, antennas and transmission lines can be added without the use of additional isolation devices. This means a tower owner can lease additional space to other wireless carriers.

On non-directional towers, an isolation system called CoLoPole typically is used. CoLoPole directly grounds an AM tower. The system benefits the AM station with improved efficiency, “air sound” and lightning protection.

Directional stations use multiple towers to form an FCC-licensed radiation pattern crucial to protecting other stations from interference. LBA has developed CoLoCoil to prevent wireless transmission lines from interfering with the operating parameters of the directional AM towers. Because CoLoCoils are modular, adding wireless equipment to a tower in the future is done systematically.

Call Lawrence Behr Associates early in planning AM colocation, because the process really begins with an analysis of a station facility. Not all AM stations are economically or technically suitable for collocation. And where multiple towers exist, choosing the optimum one is critical.
 
Because AM towers operate “hot” at high RF voltages, candidate towers must be carefully selected and worked on. (It is not true, however, that AM stations always must be shut down for installation and maintenance of collocated antenna equipment.)

The best time to call Lawrence Behr Associates is during the site acquisition stage so as to avoid unnecessary costs between the tower owner and a wireless carrier. There are numerous subtleties to negotiating a satisfactory lease or acquisition agreement. Advance screening of potential sites can also eliminate unneeded detuning situations.

Professionally managed AM collocation by Lawrence Behr Associates has been repeatedly accomplished throughout the country for such wireless carriers as Sprint, Nextel, AT&T and Omnipoint. With our help, a wireless carrier and AM host partner can fashion a long-term collocation relationship.

LBA Technology’s presentation of Kathrein / Schomandl RF Test Instrumentation generates overwhelming interest from South American visitors at the LABS’09 (Latin American Broadcast Show) going on now in Miami, FL. The MSK-200 TV signal analyzer can be seen in the center of the photo above.

LBA’s latest Authorized RF Instrument Reseller, 305 Broadcast, was also on hand promoting our products. 305 Broadcast’s President, Mr. Alfonso O Lopez and part of his sales staff preparing to engage eager visitors.

Instruments on display include:
MSK-200 TV Signal Analyzer, 3024 Power Monitor, FIT-70 In-Line Wattmeter, SafeOne Personal RF Safety Monitor. Click here for more info.

LBA Technology’s sales representatives, Javier Castillo & Paulo Fernandes waiting for the crowds.

Geographically isolated and local community analog TV watchers soon can see their favorite shows in high-definition television. The Federal Communications Commission has issued a public notice on how low power television stations can go digital, beginning in rural areas not served by full-power stations.

Though most of the American viewing public switched to DTV in June, TV translator and low power stations were temporarily exempted from the mandated analog ban. Those stations were to be given the eventual choice of switching over to digital broadcast, starting up a companion digital station, or becoming a TV translator station for a full-power digital broadcaster.

Decision time for the stations now looms, probably much to the delight of their long-suffering viewers eager to see if high-definition TV is all it is cracked up to be. Beginning Aug. 25, three kinds of applications will be accepted by the FCC:

(1) new digital-only LPTV and TV translator stations in rural areas;
(2) changes to analog and digital LPTV and TV translator stations in those areas;
(3) digital companion channels for existing analog LPTV stations.

Five months later – on Jan. 25 – the FCC will open a first-come, first-served application period for low power and TV translator stations located outside rural areas. Some of the station applications must be accompanied by a filing fee of $705 – wouldn’t you love to know how a bureaucrat arrived at that figure? – and all must be filed electronically using FCC form 346. Please note that this application schedule doesn’t preclude LPTV, TV translator and Class A analog stations from switching over to digital on an earlier schedule. In fact, the FCC is encouraging the stations to perform flash-cuts to digital any time.

The transition is not expected to occur without some awkward moments, including displacement. We’ll take this opening to plug LBA Technology’s lineup of Kathrein-Schomandl DTV test equipment, which can solve some of these anticipated problems and prevent future ones. For more information on these stellar testing devices, check out the MSK-200 TV analyzer.

Along with procedures for filing the applications, commissioners published a list of cities and geographical coordinates that rural digital LPTV and TV translator station applicants must use in siting their antennas. We hasten to suggest that local AM stations can provide a convenient tower for some of these LPTV and translator antennas. Lawrence  Behr Associates is an expert source of AM collocation solutions. Read more about it at http://www.lbagroup.com/associates/wiream.php.

Much is made of reception problems marring the changeover from analog to digital TV in the US. Typically, these problems are laid on the backs of the TV engineering community. Before you jump too hard on the engineers, please consider that broadcasting is not a technology industry – it is an entertainment industry, pure and simple! In OTA TV, engineers don’t set the course, they just follow.

Few industries in this world are so hidebound as the entertainment industry. The broadcast industry has always used regulation to throttle new technology. TV and FM survived being beaten down at birth by entrenched AM interests. Both eventually did well, ironically, leaving many of their old AM antagonists hoisted on their own petard.

We are reprising that in DTV. The marching orders for it came out in an era of big network domination, and an arrogant disregard of the real destiny of TV (CATV, mobile, SFN’s, etc.). It was birthed without much top floor regard to or respect of the many disruptive digital technologies appearing on the horizon. The voices of the forward thinkers like Sinclair were tuned out.

As a result, OTA TV as we have known it is nearing extinction, and there is little but passing political interest in the few million (1% or so) viewers with OTA reception problems. There are much bigger problems to worry about.

For one, the present system is obsolete with respect to mobile TV, some form of which will surely dominate our viewing in coming years. ClearWire’s nationwide WiMax deployments, followed by the big cell carriers coming conversion to 4G, will finish the broadcasters mobile hopes off. There just is little call for 2000′ towers and megawatts in the mobile world – 250,000+ 100′ cell sites pretty well show that!

So, back to the TV industry being in the entertainment industry.  As a product producer, the industry could care less about how they get the product to you – by CATV, FIOS, 4G, however. No industry cares to serve 100% of their market. So, in the end, it really wouldn’t have mattered if better choices had been made in the HDTV standard. Perhaps, a different technical standard would have delayed a bit the absorption of OTA TV into the broadband soup, but it will still disappear into history sooner or later.

Comments of Lawrence Behr, CEO of LBA, reflecting over 50 years in radio-TV broadcasting and wireless, representing engineering and business development consulting with hundreds of AM, FM and TV stations as well as broadband wireless enterprises. (Link to LBA Consulting Services)

The LTACT tactical communications trailer by LBA Technology is designed as a versatile budget-friendly mobile platform carrying a telescoping, storm-sturdy communications tower and an enclosed operations cabin. Custom configurable, a typical unit is the LTACT-28 furnished with a 48-foot crank-up tower, self-supporting in winds of 70 mph. A wide variety of antennas, lights, and cameras can be mounted. Outriggers stabilize the vehicle during deployment. A deck-mounted diesel-powered generator produces 10 KW of 120/240-volt AC power for over 24 hours. The 28-foot-long 7,000-pound mobile unit rides on a stable quad-tire undercarriage.

The operations cabin contains 80 square feet of temperature-controlled workspace configured as specified by the customer. LBA Technology can fully integrate and test each customer’s preferred communications system, as well.

This year at NAB2009, LBA’s channel partners and integrators featured working Schomandl – Kathrein Test Equipment in their booths. The hit of the show were the MSK-200 and ADAM-3000 digital TV signal analyzers. We bring you some photos of innovative uses of these analyzers.

ADAM-3000 in Houston CH2 Storm Tracker Hummer by TV Engineering Corp.
Television Engineering Corporation, an industry leader in SNG/ENG vehicles, integrated the Schomandl ADAM-3000 Measurement System into the Houston Channel 2 Storm Tracker H2 Hummer Satellite News Gathering vehicle on display at the show.  The feature rich ADAM-3000 was chosen to monitor and analyze satellite signals (DVB-S and DVB-S/2) to ensure signal quality in harsh conditions and provide in depth modulation analysis (QPSK,2K,8K) to maintain broadcast signal quality while pointing out issues for quick correction in zero infrastructure areas for continuing news coverage.

ADAM-3000 in Houston CH2 Storm Tracker Hummer by TV Engineering Corp.

MSK-200 Performs DVB-S2 Analysis at Evertz.
Evertz Microsystems displayed the Schomandl MSK-200 measurement system as support to its integrated digital systems presentations.  The MSK-200 was used to analyze and measure their DVB-S and S2 signal standards and provided modulation analysis for these standards using the real time constellation analyzer feature in the MSK-200.  The MSK-200 is a useful tool for these applications due to its robust feature set which not only analyzes the spectrum and modulation, but provides transport stream information and decoding to maintain optimal broadcasts and signal quality.

Transparent Video Matches MSK-200 to CATV Headends.
Transparent Video Systems incorporated the MSK-200 into their professional headend CATV systems Challenger and Challenger II.  The MSK-200 is used to analyze all CATV standards (J83A,B,C) and also provided 256 QAM Modulation analysis from the headend.  In the show demo TVS broadcast multi-channel signals from their Encoder and the MSK-200 analyzed the spectrum and provided QAM analysis to maintain, install and repair the headend systems.