TUNING IN (PDF)

 

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INFOCENTRAL

News, Trends, And Short Takes

by D. Prabakaran

 

France Adopts Two Digital Radio Formats

French Minister of Culture Mrs. Christine Albanel signed a decree to confirm the adoption of Digital Radio Mondiale (DRM) and Terrestrial Digital Multimedia Broadcasting (T-DMB) in band III and in the L-band as the digital radio standards in France. With the adoption of both technologies, France is one of the pioneer countries in the transition to digital radio.

The adoption of DRM in France is the result of long-term experiments and discussions with, or under the scrutiny of, regulatory and governmental bodies that paved the way for the decision announced by the Minister of Culture and Communication. Both T-DMB and the DRM standard were named as driving technologies and are expected to boost the commercial launch of digital radio in France, scheduled for next year.

Early in 2008, the Conseil Superieur de l’Audiovisuel (CSA) will invite tenders for radio stations and program editors to broadcast digital radio. The first digital radio programs are expected to be on air in France in the last quarter of 2008.

Radio Netherlands Worldwide To Participate
In New European Radio Station

Radio Netherlands Worldwide and broadcasters in 12 other European Union countries will launch a new European radio station soon. The station, scheduled to start in April, will broadcast daily on existing frequencies of the participating broadcasters, and will produce programs reflecting the European point of view. Programs will also be available on a special website, which will go online in June. The station will initially broadcast in English, German, French, and Polish as the main languages, with translations into five other languages. Dutch will be introduced as a main language in 2009.
The European Radio Project (ERP) has been granted a subsidy of 5.8 million euros a year from the European Commission, but the EC will have no say in the programming.

 

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WASHINGTON BEAT

Capitol Hill And FCC Actions
Affecting Communications

by Richard Fisher, KI6SN

ARRL: Misleading, Incorrect Rumors Surround IARU Band Plan

Rumors—characterized as “misleading and incorrect”—surrounded a recently revised band plan of IARU Region 2, adopted at its triennial conference in Brazil in September, according to a report in the American Radio Relay League’s ARRL Letter. In reaction, League President Joel Harrison, W5ZN, issued the following statement:

 

During the conference, held September 10–14 in Brasilia, representatives from IARU Region 2 societies met in committees prior to a final plenary session and adopted recommendations concerning a number of items important to amateur radio in the region. These included plans to improve emergency communication, enhance education and reduce interference to national emergency nets, as well as revising the Region 2 high frequency band plan.

The band plan can be viewed on the Internet at www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf.

The revised Region 2 band plan for 160–10 meters took effect January 1. “The band plan is based on the band plan adopted by IARU Region at its conference in Davos, Switzerland, in September 2005,” the statement said.

“IARU regional band plans have been in existence for many years,” the ARRL reported. “They are developed, reviewed and approved at regional conferences of the IARU Member-Societies. The band plans provide voluntary guidelines and recommendations for good operating practice that are intended to assist amateurs in making the most effective use of our limited frequency allocations. They are not restrictions and carry no regulatory authority.” The ARRL also stated:

 

One virtue of voluntary band plans is that they are more flexible and can be amended more easily than the FCC rules; writing them into the rules would be counterproductive. As voluntary guidelines, the band plan cannot by definition be “more severe” than regulations; however, if the band plan did not suggest an operating pattern that is a subset of the regulations, it would serve no purpose.
There is also a mistaken assumption that the new IARU Region 2 band plan is an ARRL initiative seeking regulation by bandwidth. It is not, nor is it in any way a vehicle to achieve regulation by bandwidth.

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On With The (Air) Show!

The Warbirds Fly High—The Mustangs,
Blue Angels, And Thunderbirds Wow
The Crowds Below

by Tom Swisher, WA8PYR

 

Held at Rickenbacker International Airport in Columbus, Ohio, from September 27–30, 2007, the recent Gathering of Mustangs and Legends was for me the ultimate air show. A once-in-a-lifetime opportunity to see many classic warbirds fly and meet the legends who flew them in combat, this past GM&L also marked the 50th birthday of the U.S. Air Force and the 55th anniversary of the founding of the Northeastern Training Center, a B-17 training base later renamed Lockbourne Air Base, and later still Rickenbacker Air Force Base.

GM&L was sponsored by Stallions 51, a company that restores and flies World War II era P-51 Mustang fighters. The event brought together over 100 of these classic fighters, other classic fighters like the P-38 Lightning and P-47 Thunderbolt, classic warbirds like B-17, B-24, B-25, and Lancaster bombers, C-47 cargo aircraft, and vintage ground vehicles like tanks, trucks, and support trailers. There were also modern aircraft like C-5, C-17, and C-130 cargo planes; a KC-135 tanker of the locally based 121st Air Refueling Wing; A-10, F-15, F-16, and F-22 fighters, and even a B-52 bomber!

Shows by various civilian and military flight teams capped the event. The real highlight of the event, though, was seeing the planes in flight and having the honor of exchanging a few words with the pilots who flew them. It was the ultimate air show and well worth the experience.

From County Fair Barnstorming To The Military’s Precision Maneuvers

At this point, you might be asking “what’s an air show?” Simply put, an air show is an event where you can see airplanes, both flying and on display.

But, in reality, an air show is much more than that. Since that first powered flight at Kitty Hawk, aviators have put on shows to demonstrate their machines and their flying skills for the entertainment of others. We may take airplanes for granted today (and whine about them when they’re late), but in the early days, any airplane was a great novelty, and an air show was an often-touted part of county fairs and other local events. An enterprising aviator would fly his airplane over and perform a few simple maneuvers for the crowd, usually causing great excitement. Through the 1920s, air shows would feature aircraft displays, aerobatics, and often death-defying stunts such as wing-walking and barnstorming.
 

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LPFM’s Rallying Cry—
Low Power To The People!

The Prometheus Radio Project Raises
The Barn For Community Access

by Kate Blofson, KB3PYW

 

If you had asked Pete Tridish, KB3LNS, of the Prometheus Radio Project 10 years ago where he thought he’d be in 2007, I’ll bet you a Crown FM 300 broadcast transmitter that he would not have said heading down to Washington, D.C., at the drop of a hat to meet with FCC Chairman Kevin Martin. Tridish, a former radio pirate who lives in Philadelphia, is a founding member of the Prometheus Radio Project, an organization that works primarily on Low Power FM (LPFM) radio. His title? Director of Electromagnetism.

Operating with a small staff and limited budget from a church basement in West Philadelphia, Prometheus has become the leading organization advocating for LPFM, its scruffy activists suiting up to visit Congress and the FCC to promote the value of local community radio.

LPFM In Action

The FCC began issuing licenses for the Low Power FM Radio Service in 2000 to increase community access to radio and to add new voices and perspectives to the FM dial. These small stations operate at 100 watts, with a service area of five to 10 miles. As a non-commercial service, LPFM licenses are held by nonprofit organizations like schools, churches, civic groups, and, yes, even a couple of amateur radio clubs. LPFM owners are supposed to live in the community they serve, and stations must originate at least eight hours of local programming each day. There are currently over 800 LPFM stations on the air across the country, serving their communities with local news, music, public affairs, special interest shows, religious services, and talk.

While there was some abuse of the FCC’s intention with the service, scroll through a list of LPFM stations and applicants at www.lpfmdatabase.com and you’ll find a variety of groups that reflect the wide range of local organizations in American communities: high schools and universities, libraries, Native American tribes, local churches, environmental, civil rights and farmworker groups, arts organizations, municipalities—you’ll even find a Drum and Bugle Corps in Ohio and the Scottsdale Italian Social Club in Arizona. And where you find a low power station—if you’re lucky enough to have one in your area—you’ll likely find a ham or other radio enthusiast who’s involved.
 

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TECH SHOWCASE

 

An Innovative License-Free Alternative To FRS/GMRS

The TriSquare TSX300 900-MHz
FHSS Handheld Transceiver Is
Positioned To Dominate The Consumer
Two-Way Radio Market

by Bernard Bates

 

PopComm’s November 2007 cover story, “Digital Two-Way Radio Technology Reaches Consumer Market” covered the emerging trend of new 900-MHz FHSS (Frequency-Hopping Spread-Spectrum) radios becoming a serious license-free alternative to FRS/GMRS radios. Picking up where that article left off, this article will review one such radio, the TriSquare TSX300.

This new handheld transceiver sets a new price/performance standard, using innovative digital technologies to offer many features we’re accustomed to seeing only in PCS/cellular handsets. It’s about time two-way radio users and hobbyists started benefiting from these exciting new personal communications technologies.

FRS/GMRS Problems Create Opportunity

Back in 1999, TriSquare was a major OEM manufacturer of FRS/GMRS radios for several companies marketing under various well-known brand names. As the popularity of FRS/GMRS radios skyrocketed over the next five years, the market approached saturation and profit margins dropped to unsustainably low levels. And, not surprisingly, the widespread use of 50 to 80 million FRS/GMRS radios created severe congestion on the 22 FRS/GMRS channels at crowded events, metropolitan areas, and elsewhere. Tens of millions of users, including many large and small businesses, blatantly violated FCC regulations by using GMRS channels without obtaining the required $75 license, or by using FRS channels for business purposes.

At the same time, many FRS/GMRS radio users became increasingly aware of the glaring feature disparity between their simple two-way radios and their feature-rich cell phones (which offered private and interference-free voice communications, text-messaging, caller ID, call waiting, contacts lists, hands-free operation, ringtones, vibrating alerts, etc.).

Engineering A Solution

In 2004 TriSquare started engineering a solution. Its years of experience designing DSP (Digital Signal Processing) and SDR (Software-Defined Radio) technologies into consumer two-way radios, and the falling cost of digital components needed to implement these technologies, convinced the company that it was feasible to build feature-rich FHSS two-way radios for the consumer market to supplant FRS/GMRS. DSP and SDR technologies allow advanced features and functions to be designed and implemented in software, and then duplicated in firmware, at far lower cost than using many dedicated electronic components.
 

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SCANTECH
The 700 MHz Shuffle

by Ken Reiss 

No doubt you’ve heard about the 700-MHz spectrum. You might also be aware that there are plans for public safety frequencies contained in the 700-MHz band, and perhaps you’ve been concerned about getting a radio that covers those frequencies so you’ll be all set when they spring to life. Or perhaps you’ve not paid attention to any technology news for a while and have missed the whole thing. I have to admit I wasn’t paying real close attention until this latest round of headlines. Let’s see if we can figure out what is and is not going to happen on these prime frequencies.

The Plan

This sudden interest in 700 MHz has been sparked by the fact that it appears we’re really going to get around to switching to digital television sometime in the next year or two (I thought we were good for one or two more extensions, but who knows for sure). Part of the provision for doing that is that the conventional TV Channels 52 to 69, or 698 MHz to 806 MHz, will be freed up for re-allocation. That’s just over 100 MHz of space in a very prime UHF region, so there’s been a lot of interest in getting control of it.

The good news is that no one entity will in fact have control over the whole thing, but prominent in the recent news is the speculation about, and close watching of, just who is interested in pieces of it. No fewer than 200 separate applications have been filed with the FCC for portions of this band, and the minimum bid for the auction is 4.3 billion. That’s billion…with a B. Some serious players are interested in this space as it represents a gold mine that, ultimately, you and I will pay for.

For purposes of the auction(s), the band has been divided into lower 700, from 698–746, and upper 700, from 746–806. The upper portion represents TV Channels 60 through 69 and was supposed to be vacated first. The lower portion comprises TV Channels 52 through 59 and was supposed to be vacated later, but apparently in some areas it is already vacant and being transitioned to new purposes. There were previous auctions to deal with those frequencies.

These upper and lower segments are themselves further divided into blocks, A–E in the lower and A–D in the upper band. Confused yet? Just wait. Some of the blocks had been previously auctioned off and are not under consideration now. It happens that Blocks A, B, and E in the lower band and C and D in the upper band are what’s up for grabs in the current auction. So some of each is being sold, but they’re not together (if you follow my drift), nor do they mean much other than a group of frequencies auctioned at once.
 

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 THE ANTENNA ROOM

Air Band Antennas

by Kent Britain, WA5VJB

 

Apparently, there are quite a lot of aviation comms fans out there among our readers. I never realized just how popular it is to listen on Unicom Channel or to the local airport control towers. I have personally avoided communicating with control towers since I sold off my half of an Aerocoup years ago, but our valued readers have spoken, and this construction project was suggested by one of them.

In Photo A and Photo B you see a two-element and a three-element Yagi antenna designed around 125 MHz, but they have more than enough bandwidth for the entire VHF comm band.

In Plot 1 you see a network analyzer plot of the two-element Yagi. The -10 dB line represents about a 2 to 1 SWR, and the -20 dB line represents about a 1.2 to 1 SWR. As you can tell, we have a pretty good SWR over the aircraft VHF communications band.

Construction

If you’ve been following “The Antenna Room” columns, you know I like to use that J-shaped driven element on my beam antennas, but this time we’re going to use a simple dipole driven element. For you folks who already have antenna modeling software, yes, I’m again using element-to-element spacing to load the 72-ohm driven element down to 50 ohms. Most Yagis have different stubs, bars, or capacitors on the driven element to impedance-match the driven element to the 50-ohm coax, but this design uses the construction of the Yagi itself and the distance between elements to do the impedance matching for you. Just build per the dimensions and put it up.

For the elements I used bronze welding rod, but just about any stiff wire will work. Aluminum rod from another antenna, coat hangers, copper wire, hobby tubing, or thin water tubing can all be used. Heck, I even used clear plastic tubes full of salt water, but that’s a story for another column.

Because 48 inches is kind of long for most rods and tubes (they seem to come in 36-inch lengths), I just drilled two holes in the boom, pushed them through, and as you can see in Photo C, just soldered a strap between the two. This shorts out the two pieces and makes it one long element.

The elements can be between 1/8 and 1/2 inch in diameter without changing performance. For the driven element you really want to use a material you can solder to. Again, I used bronze welding rod, which solders pretty well, but it’s possible to make some clips out of brass or tin and solder the coax connections to the clips. In Photo D you can see where I have the coax shield soldered to one element, and the center conductor of the coax to the other element. You want to use RG-58, RG-8X, RG-8, or some other 50-ohm coax. If you plan to mount the antenna outside, I would suggest some RTV or similar glue on the open part of the coax shield to help keep water out of the coax.

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BROADCAST TECHNOLOGY

The ARTV Monitoring Center

by Bruce A. Conti

 

Imagine earning a living by monitoring broadcast signals. The FCC once manned monitoring sites across the country until budget cutbacks and downsizing put an end to it. The FCC now depends on self-monitoring by the broadcast industry. BBC Monitoring might be an option, but it’s primarily a news gathering agency. How ’bout the broadcast monitoring center of Radio Televizioni Shqiptar, or RTSH (Albanian Radio and Television, or ARTV)? It’s an elite group in Albania responsible for monitoring everything from AM radio to satellite TV broadcasts from a technical standpoint.

Background

The ARTV Monitoring Center of Radio Tirana was first created by the Chinese in 1966 and installed at the Albanian Telegraphic Agency (ATA) receiving station in Kamez Field, eight kilometers northwest of the capital city of Tirana. It was transferred to the Radio Tirana headquarters in 1993. The Monitoring Center has been working under the supervision of the government Directory of Radio and TV Transmitting Stations-Tirana from 1966 to 1994, under the Directory of Radio Tirana from 1994 to 1998, and thereafter again as an extension of the Directory of Radio and TV. The staff consists of a chief electrical engineer and four operational technicians.
Present duties of the ARTV Monitoring Center include keeping under continuous interactive technical control the technical quality of the following radio and TV broadcasts: Radio Tirana Channel 1 on MW-Shijak (ceased on February 3, 2006), on FM-Dajt and via satellite, Channel 2 on FM-Dajt, and Channel 3 (Radio Tirana International) on MW-Fllakë and SW via Shijak; Foreign broadcasting by the BBC on FM-Dajt, VOA on FM-Dajt, Deutsche Welle on MW-Fllakë, TransWorld Radio (TWR) on MW-Fllakë and HF-Shijak, and China Radio International (CRI) on MW-Fllakë; and Radio Televizioni Shqiptar via Dajt on VHF-I, VHF-II, and UHF; and TVSH on satellite. The Monitoring Center informs the relevant sectors and directors immediately of irregularities and problems during the transmission of programs, with daily written reports provided by the head of the Monitoring Center.

International Collaboration

Previously a Communist nation aligned with the Soviet Union and later with China, government reforms led to democratization of Albania in the 1990s. For the first time, in April 1995, international monitoring cooperation with many other radio monitoring centers in Europe, the Middle East, and North America was established by exchanging reception reports and technical data on reciprocal radio and TV broadcasts.
 

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POWER UP: RADIOS &
HIGH-TECH GEAR

New, Interesting, And Useful
Communications Products


Comet Antennas Quad-band
Rotatable Trapped Dipole

Comet Antennas is offering the H-422 quad-band rotatable trapped dipole with frequency coverage including the 40-, 20-, 15-, and 10-meter bands. For better performance, the 7-MHz band is independently tunable, while the 14-, 21-, and 28-MHz bands tune simultaneously to low, mid, or upper band ranges.

It features a compact design for easy installation, even in antenna restricted locations, and can be assembled in either a “V” or “straight” configuration (the “V” shape achieves good performance at a minimum of 10 feet above ground). Additional features and specifications include VSWR: less than 1.5:1 at center freq; Impedance: 50 Ohms; CBL-2000 2kW Balun included; Length: Assembled in “V” shape: 24' 5"; Assembled “straight”: 33' 10"; Weight: 11 lb 14 ozs; Max Power: 1000W SSB / 500W FM; Max Wind Survival: 67 mph; Wind Load: 9.9 sq feet.

Construction is of telescoping aluminum tubing with extruded aluminum/stainless steel mounting hardware included. A mast diameter of 1.25 to 2.5 inches is required. Three pre-drilled radiator lengths are provided for easy tuning.

For more information on the the H-422, which retails for $389.95, contact NCG Company at 800-962-2611 or via email at micks@cometantenna, or visit their website at www.cometantenna.com.

Wilson Electronics’ New
Cell Phone Cradle Plus

Wilson Electronics, a manufacturer of cellular amplifiers and antennas, has introduced the new Cradle Plus, a cell phone car cradle with a built-in antenna. When combined with a Wilson amplifier and an outside antenna, the Cradle Plus accommodates any hands-free device and offers improved cellular signal and increased driver safety in any vehicle.

The outside antenna communicates with the cell site, and the built-in cradle antenna communicates with one or multiple cell phones, depending on the amplifier used, significantly improving cell phone performance. With up to 10 times more power than a typical cell phone, the system extends signal range and strength, allowing users to communicate reliably in places they never could before.
 

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GLOBAL INFORMATION GUIDE

More From Moldova And Monrovia, And Still More…

by Gerry L. Dexter

 

A couple of years ago a station known as Radio PMR, headquartered in the breakaway portion of Moldova, was active on shortwave. It didn’t last long before disappearing from the airwaves. Now it’s back with something of an international service. Radio PMR is operating according to a schedule consisting of 15-minute segments of English, French, and German beginning at 1500, 1600, 1700, 1800, and 1900 on 7370. These, obviously, are not opportune hours for us in North America (unless you have your feet in the Atlantic Ocean). However, the station also offers similar fare at 2300 and 0000 on 6240, which some are reporting at excellent strength (here in Wisconsin the S-meter went to attention when the carrier came on around 2254 the other night).

The transmitter is that 500-kW monster at Grigoriopol in the Trans-Dniester region, a site also used by Moldovian Radio and some of the Voice of Russia broadcasts, among others. Radio PMR studios are in Tiraspol, in the Pridnestrovian Moldavian Republic, a “country” which has not achieved much in the way of diplomatic recognition.

Another old friend has reappeared. ELWA in Monrovia, Liberia, recently returned to the air. Over the past couple of decades ELWA had twice been destroyed in the country’s horrible civil wars and twice has returned, refusing to be a victim of still another African warlord. This most recent return, however, wasn’t due to a conflict but rather was by design, the downtime the result of a new transmitter installation, which probably required more time to complete than originally planned. Whatever the reason, it’s nice to have ELWA active again back on its old 4760. It can sometimes be heard in our late afternoons, especially by you ESTers. The rest of us are more likely to find it at its 0600 morning sign on.

Ethiopia’s Radio Fana has added a third frequency, 5970, to its 6110 and 7210 dial spots from sign on just prior to 0300. None of the three produce speaker-shaking signals; you’ll have to dig a bit to come up with anything.
International Radio Serbia is once again broadcasting from its own in-country site at Bijeljina. There’s just one 250-kW transmitter operational here at present, using 6100.

Don’t hold your breath, but way, way down the road we may see the resurgence of Radio Ghana. The station says there are plans afoot to bolster its shortwave service with a 50-kW transmitter. Ghana is shown as currently active with up to 50 kW on 4915, but my guess is that “inactive” is a more accurate description, since it’s almost never reported. So this boils down to information you can just file away in case GBC does show up in rejuvenated form down the road.

The All India Radio outlet at Gauhati (4940, 7280, and 7420) is off the air temporarily, according to an Indian SWL. There’s no word on why or whether a return is expected.
 

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THE PROPAGATION CORNER

Coronal Holes As Prop Puzzle Pieces

by Tomas Hood, NW7US

 

Coronal Mass Ejections (CMEs) play a major role in the propagation of radio waves, especially in the world of shortwave radio. CMEs carry millions of tons of plasma from the sun’s polar regions, some of which collides with the magnetosphere that surrounds our planet. Under the right conditions, this solar plasma enters the atmosphere, changing the ionospheric conditions, sometimes even causing aurora.

The sun’s magnetic field permeates the entire solar system, and beyond, in a giant “bubble” called the “heliosphere.” The heliosphere is created by the solar wind, which is always blowing out away from the sun. This solar wind contains magnetic field lines that also originate in the sun. These magnetic fields interact with the Earth and Earth’s magnetic field, which is known as the “magnetosphere.

The solar wind consists of ionized atoms from the solar corona, as well as these magnetic fields. As the sun rotates once approximately every 27 days, the magnetic field transported by the solar wind gets wrapped into a spiral, called the “Parker spiral” (see photo). The sun’s huge magnetic field is known as the Interplanetary Magnetic Field (IMF), and is a primary cause of space weather. The plasma that escapes or is blown away from the sun rides the IMF on the solar wind.

As Earth orbits the sun, it dips in and out of the wavy current sheet of the Parker spiral. The spiral’s magnetic fields have polarity. On one side of the magnetic field, the field is oriented to the “north,” or toward the sun. On the other side it points “south,” or away from the sun. The IMF’s orientation at the point of measurement is indicated by an index that solar scientists label Bz. When the Bz is negative, it indicates a southerly orientated IMF; when positive, it indicates a northerly oriented IMF.

South-pointing solar magnetic fields tend to “magnetically reconnect” with the Earth’s own magnetic field (the magnetosphere), at the point where the two fields interact. This allows the solar wind, and the plasma riding on the IMF, to flow in to the magnetosphere and collect in a reservoir known as the boundary layer. The energetic particles riding the solar wind can then penetrate the atmosphere, causing aurora, and triggering geomagnetic storms. If the IMF is oriented northward, however, this magnetic reconnection does not take always take place. Yet, if the pressure of the shock wave from a passing CME is great enough, even with the IMF oriented northward, the geomagnetic field will become disturbed.
 

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HAM DISCOVERIES

From Hamfests To Solar Cycles—
Spring Has Sprung!

by Kirk Kleinschmidt, NTØZ

 

Whether solar Cycle 24 is picking up steam or still taunting us with its promise of ionospheric goodness, spring has definitely sprung here in the frozen North. (As I write this, my “mouse hand” is a bit sore from chipping ice off the sidewalk, a December hazard in southern Minnesota.) It’s the start of hamfest season, at least above the Mason-Dixon Line, and hams, and groundhogs, are poking their heads out of their burrows, hoping to catch a glimpse of spring.
I’ve written about hamfests for the past 19 years. And my universal message to hams new and experienced alike is: Get out there and get involved. But if you’re a newcomer to the hobby, you might be wondering what’s in store. Good point!
Hamfests are like the state fairs of amateur radio. There’s a lot going on, including, seminars, flea markets, demonstrations, licensing tests, “eyeball QSOs,” and more, all in an atmosphere of camaraderie and good food!
At ham radio flea markets you’ll find hundreds (sometimes thousands) of fellow hams, tons of bargain-priced radio and computer gear (including hard-to-find components and electronic assemblies), interesting forums and lectures, ham radio exams, and tasty grilled sausages. The exact mix of the things you’re likely to find depends a lot on the kind of hamfest you’re attending, its size, and to some extent, the region of the country.
Large multi-day hamfests, such as the annual Dayton HamVention or the many ARRL Division Conventions, attract thousands of hobbyists. Local hamfests may draw only a hundred. But the fun factor is universal, regardless of size.
Most hamfests have a swapfest or flea market where hams and dealers set up shop. Most are also piled high with computer stuff, from obsolete parts to new systems. Computer technology is forever merged with amateur radio, so worrying about the number of computer vendors at hamfests is a moot point. Why not take a look at everything?

Hamfest Schedules

Information about upcoming hamfests is available from several sources. Members of your local ham club will probably be “in the know,” especially when it comes to nearby happenings (hamfests tend to be annual events, publicized well in advance). Nationally, dozens of hamfests and amateur radio events are listed in our sister publication CQ and also QST magazine. You can browse hamfest listings electronically at www.arrl.org/hamfests.html or at the World Radio website, www.wr6wr.com/.
Hamfests are typically held at hotels, schools, parks, National Guard armories, fairgrounds, or civic centers. Organizers usually host events at identifiable and accessible locations (although sometimes you’ll be surprised!).
Sparsely populated parts of the country tend to be a bit starved for hamfest opportunities, while high-tech centers like the Boston area (with MIT and all) and Silicon Valley seem to have as many hamfests as yard sales. For all its hassles, population density has an advantage or two...

 

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HOMELAND SECURITY

A Systems Approach To Mobile EmComm

by Rich Arland, W3OSS

 

Last month we started a multi-part series on outfitting our Scamp camp/travel trailer with radio gear, supplemental power, antennas, and accessories necessary to perform emergency communications (EmComm) duties during exercise or real-world disaster scenarios. During my 20 years in USAF Comm Command, I was trained to regard communications as an entire “system” rather than a transmitter, receiver, antennas, transmission medium, etc. Taking the “systems approach” in turning our tiny Scamp camper into a mobile comm facility makes a whole lot of sense for a number of reasons, and luckily both my wife, Patricia, and I are now retired and so have the time to devote to EmComm training and deployment.

Even though our Scamp/comm facility would be only one part of the overall picture in a possible emergency situation, it would serve a vital role in furnishing communications to the various served agencies that would be involved in mitigating a disaster. We are fully self-contained and can function independently of any other system. Therefore, we need to regard our Scamp not only as part of the system, but as a mini-system within the bigger disaster mitigation system.

EmComm—A Systems Approach

Since we’re going to take a systems approach to our Scamp project, we can now start breaking things down into bite-sized chunks for easy digestion. The radio gear, of course, is vital, but it’s only part of the Scamp system. We also need antennas, feedlines, and power, plus some operator/creature comforts, just to name a few things. All these and more need to be factored into the Scamp equation.

Last month we looked at the rationale of how I ended up deciding to use ICOM IC-706 transceivers. Of course, having the same (or similar) radio gear in each vehicle AND the Scamp/comm facility makes it easy for operators to transition from one station to another without having a steep learning curve. During the extreme stress of a real-world disaster, the less distraction you have to deal with the better. In the case of radio gear, if you’re already using one piece of equipment, an IC-706 or anything else, in your normal operating, adapting the same rig to your mobile EmComm environment poses virtually no problems. The controls are all the same, the ergonomics are identical, muscle memory takes over and you find yourself working the new station like a seasoned pro. Life is good!

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THE POP’COMM TRIVIA CORNER

Radio Fun And Going Back In Time

by R.B. Sturtevant, AD7IL

 

Q. Who was the first person to have a CB license and why did he get it?

A. The first CB license was awarded to Al Gross, W8PAL, who had lobbied the government for years to create a license class for use by businesses that needed mobile and handheld transmitters. His Gross Electronics had several patents for various portable and cordless telephone devises. In September 1958 Gross Electronics was granted the first FCC license on the new Class D 27-MHz Citizen Band.

Many of Gross’ fellow hams felt he had let the ham community down because the new frequencies came from the old 11-meter ham band. Nevertheless, Al Gross operated on both amateur and CB bands until his death in December 2000. His CB handle was Phineas Thaddeus Veeblefetzer after the eccentric inventor Phineas Fogg in Jules Verne’s Around the World in 80 Days.

 

Q. What is meant by the term “hitchhiking” in clandestine radio operations?

A. Turning on your transmitter on the same frequency as an enemy radio station after the “other guys” go to bed. Late listeners may think that they’re still listening to “their” station, rather than “your” radio station. “Surfing” is putting your signal next to the other guys so that if the listener doesn’t tune closely he gets you instead of “them.”

Q. You’ve said that one of the key operations of the British Navy and Colonial Armies in World War I was to break up the German wireless system to keep them from communicating with their colonies. Most of the German colonies were in Africa and the South Pacific. How was it done?

A. At the beginning of World War I there wasn’t much going on in German South-West Africa. There was some copper mining, and a few diamonds had been located. These, however, were not worth taking Germans troops off the western front to defend. There were, however, three major wireless stations in the colony, which were very important. The German Navy had 17 Naval cruisers with the responsibility to guard the sea lanes between Germany’s colonies in the South Pacific, China, Africa and The Fatherland. Wireless stations kept the fleet in touch with Berlin from the Southern Hemisphere.

 

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RADIO RESOURCES

All About Your Own Marine Shore Station License

by Gordon West, WB6NOA

 

If you live near a seacoast or waterway, you likely tune in to ship stations transmitting on marine VHF as well as long-range marine single sideband frequencies. But did you know that the FCC allows coast (shore) stations to legally transmit from shore to ships? You yourself might qualify for an FCC coast station license, and you may not need the services of a commercial licensing company to get you through the FCC process! We’re still a couple of months away from warm weather boating, so now is the perfect time to sit down at the computer and “license-up” for VHF and SSB shore-to-ship communications.

Who Qualifies

Subpart K, FCC Rule 80.501 describes the eligibility requirements for a shore-to-ship coast station license. If you have a REAL requirement to talk from a shore radio station to ships at sea or nearby boats in the harbor or on a lake, you’ll need to meet at least one of the following eligibility requirements:

• You run a marina with boat slips
• You run a launch ramp
• You fix electronic equipment aboard a boat
• You fix ANYTHING aboard a boat
• You run a port or waterway
• You run a boat rental or charter business
• You run a drawbridge
• You assign buoys for mooring
• You run a yacht club
• You run a gas dock or marine repair facility
• You sell live bait
• You run an emergency medical water rescue agency
• You rent fishing poles
• You rent water skis and inflatable tow rafts

You will NOT qualify if:

• You just want to yak with anyone out on the water
• You have absolutely nothing to do with boating, but always
wanted to own a yacht
• You want to help the Coast Guard when someone yells MAYDAY
• You just want to hang some FCC wallpaper in you ham shack

More Than Just Commercial Reasons

“Having more VHF and SSB shore stations guarding the distress channels will add to our listening watches,” said U.S. Coast Guard Telecommunications Joe Hersey. He agrees that more marine dockside businesses listening on VHF Channel 16 will mean a better chance that someone overboard with just a submersible VHF handheld may be radio-rescued.
 

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REACT IN ACTION

Helping Others Helps You, Too

by Ron McCracken, KG4CVL / WPZX486

 

You join a REACT Team to help others, right? Right, but you will almost certainly learn a great deal that will help you as well. Perhaps the first thing you’ll learn as a REACT volunteer monitor is that very few operators know how to capitalize on their radios in emergencies. Too often, you hear callers simply yell “Help!” If they’re too distant to hear you asking for key details, like location and problem, the radios most of them bought with safety in mind will bring no help.

One California REACT Team reported that in a given month 94 percent of the distress calls its volunteers monitored failed to get sufficient information across to send assistance. Imagine their frustration. The REACT monitors heard each one, but the callers gave no critical details (exact location, problem, name). In that mountainous terrain, callers could not hear REACT monitors asking in vain for the needed information. The calls failed. Needlessly.

Yes, you learn fast as a REACT volunteer that in an emergency you must broadcast repeatedly WHERE exactly you are and WHAT is wrong. That knowledge alone could save your life some day. You learn that distance, terrain, and/or weather can prevent callers from hearing police or REACT monitors. Those monitors are totally dependent on the caller to air repeatedly essential details monitors must have in order to send help. This applies whether you’re using CB, FRS, GMRS, or any other type of radio.

Precious Lessons

Another lesson REACT volunteers quickly learn is that “skip” propagation can be an ally or an enemy. You won’t serve too long as a REACT monitor before you encounter “skip shooters” trying to contact distant stations. They can be hundreds of miles away and unaware that they’re making it impossible for you to handle local distress calls where lives may hang in the balance.

The flip side is that skip may bring you a distress call from far away. You learn to keep a road atlas handy. If the distant caller knows his emergency radio procedure, you may have the privilege of alerting authorities to his plight.
 

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 THE WIRELESS CONNECTION

A Simple AC Current Sensitivity Multiplier:
An Easy Weekend Project You Can Build!

by Peter J. Bertini

 

There’s a new “guy” kind of toy store that opened a few months ago near where I work: a Harbor Freight retail outlet. While most of the items offered are “imported,” and thus perhaps more aligned with the needs of bargain hunters, I still get a rush when window-shopping the endless shelves piled high with inexpensive equipment and tools. It’s fun to role-play Tim Allen, of the Home Improvement TV show fame, and imagine what home projects could be successfully undertaken if backed by an arsenal of manly power tools!

The Harbor Freight Cen-Tech Digital Clamp Meter

An item there recently caught my eye. Harbor Freight’s Cen-Tech digital clamp meter was on sale for several dollars—a deal I could hardly resist!

In my professional life I use one of several Fluke digital meters with a companion Fluke Y8100 AC/DC current probe. The Y8100 is a very sensitive device, and it’s also capable of measuring DC current. To show the differences, Photo A contrasts the self-contained Cen-Tech clamp-on meter to the Fluke clamp-on probe, which requires a separate companion meter. But few hobbyists really need a clamp-type meter often enough to justify buying one. When they fail, it will cost more to replace the three lithium cells that power the meter than I paid for the meter itself. I consider it an expendable throwaway item! Note that while the package incorrectly advises that batteries are not included, I found that they were indeed packed inside when I opened the bubble packing.

What It Can Do, There Are Limitations…

Let’s take a look at the Cen-Tech clamp meter to see what it can do. It has two ohmmeter ranges, with a diode check, and will read resistances up to 200K-ohms. That’s not much use for radio work, since we often encounter resistor values of 1 megohm or higher. Ditto for the DC voltage range, which is 300 volts. Many transformer sets will have voltages that are well over 400 VDC. Strike two! Sigh.

 

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UTILITY COMMUNICATIONS DIGEST

A Look At The High Frequency Beacon Society

by John Kasupski, KC2HMZ

 

If you live in the northern latitudes as I do, the month of March is welcomed as a time when things begin to clear up a little. By that, I mean things such as the weather, or perhaps those mountainous piles of snow on either side of your driveway. However, since March is already a “clearing up” month for many of us, it’s only fitting that we use this month’s column to clear up a few things concerning our radio activities as well.

We’ll begin this tidying-up session with a look at the High Frequency Beacon Society, because they’re the folks behind some of those mysterious beacon stations many of us have logged and wondered about the origins of.

Simply stated, the High Frequency Beacon Society is a private organization of radio experimenters whose aim is to study the propagation of shortwave beacons. To do this, the Society’s members have placed on the air a number of low-power (usually 100 mW or less) HF beacons, in various locations around the continental United States. These beacons, as we shall see, are often of the “homebrew” variety—the spirit of radio experimentation being very much alive among the Society’s members—and lately have been getting noticed more frequently by contributors to the readers’ logs that accompany this column every month.

Table 1 is a list of the High Frequency Beacon Society’s beacons that were operative as of this writing. However, the Society reports that new beacons are being constructed and put on the air often, and since they are experimenters, beacons may go on and off the air at any time. Therefore, it’s recommended that you check the Society’s website for the most up-to-date information before you start listening for a beacon that may no longer be on the air—or neglect to listen for one that is! I’ve included the URL for the website in the table; once there just click the “Beacons” button to see the current list of listening targets the Society’s experimentation is providing.

In addition to facilitating the study of propagation, these beacons provide listeners with a bit of a challenge, since these are very low-powered transmitters. As the Society notes on its website, “copying weak signals requires many unique skills and we salute the listeners who dig out these beacons.” They’re not just paying lip service to the skills needed to dig these weak signals out of the mud, either. Send your listening reports and sound files to hiferbeacon@yahoo.com and it’s possible you’ll receive QSL cards from beacon operators!

 

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LOOSE CONNECTION

Now That Bears Repeating

by Bill Price, N3AVY (and Son)

 

My HPJIE* brought me in from a well-deserved vacation to find out why one of our repeating transmitters was not repeating as it should. You may remember from previous episodes that my knees (and some say my, er—girth) will not let me climb beyond about 10 feet. For that, we hire our friends at US Tower, who are by far the best and most professional climbers and riggers I’ve ever met. If I may be serious for just a moment (ok—time’s up!) I’m pleased to give them a little plug.

So the boss and I make sure that the main transmitter is transmitting, and is doing what it should. We have learned to check and double-check all the obvious things on the ground before calling in the acrobats to check transmission lines, connections (kindly remember the name of this column), and antennas. We have learned to assume nothing, and to actually look at the signal going into the transmitter, and at the signal coming out of the transmitter, and the signal coming out of the antenna before driving the two hours of traffic, steep hills, and mud to the repeating transmitter site.
And when we get there, we look for bears before climbing out of the truck. We have never seen any, but we know deep down that they are lurking behind every tree, waiting for a chance to eat us alive and steal the truck for a weekend of joyriding before running out of gas. In my heart, I know that my life will eventually be portrayed in a Gary Larsen cartoon.

Unlike the last time, one of us remembered to bring the keys to open the gate and the door to the transmitter building. We see that no signal is being received, therefore, none can be repeated, yet we know that the main transmitter is sending a lovely signal toward us. We are sure. Well, pretty sure. We verified that there was a signal, but neither of us bothered to check the output power.

We are now sure that the problem lies in the receiving antenna. Or the receiving converter. Or the receiving line. Or maybe the transmitter is not putting out as much as it should, because we can see a weak signal where we should see a strong one. Then again, recent storms may have blown either of the directional antennas off their intended path; it wouldn’t take much—just a few degrees on either end would do it.

 

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