TUNING IN (PDF)

 

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INFOCENTRAL

by D. Prabakaran

News, Trends, And Short Takes

 

BBCWS Closes Remaining Shortwave Transmissions To Europe

The BBC World Service (BBCWS) announced on its website that the remaining BBCWS shortwave transmissions to Europe would close as of February 18, 2008. The BBC said the change was in line with listener trends in radio. Increasing numbers of people around the world are choosing to listen to radio on a range of other platforms, including FM, satellite, and on line, with fewer listening on shortwave. This is particularly the case in Europe, where the majority of shortwave transmissions ceased in March 2007. The current closures affect the remaining transmissions heard in southern Europe. Frequencies for western Russia remain, however, and listeners in southeastern Europe may be able to pick up frequencies for the Middle East when atmospheric conditions permit. BBC DRM digital shortwave transmissions to Europe will continue for the time being.

Special Swiss Radio Station To Operate For Euro 2008

A special radio station will operate in June aimed at uniting football fans from all the countries participating in the Euro 2008 tournament. Radio 11 will run only during the competition, offering a diverse mix of music from the 16 nations and tips for supporters on where to go and what to do while in Switzerland. The station’s “Rhythm of Football” motto hopes to set the tone among fans attending the European championship, co-hosted by Switzerland and Austria from June 7 to 29.
Radio 11 will be broadcast mainly in English, French, and German, but also in other languages on match days. The music selection will also reflect whichever countries are playing on particular days. The music content was be available online as of the middle of February, but the radio frequencies beginning in June in the host cities of Zurich, Bern, Basel, and Geneva are not yet decided.

Radio Sweden To End German Service

Radio Sweden has confirmed that its German service, which has been on the air for 69 years, would close at the end of March. Within international broadcasting, some languages, including German, have had a breakthrough on the Web and through podcasting, but the number of listeners, especially on shortwave, has dropped dramatically in recent years. This development figured in Swedish Radio management’s decision of to suspend German broadcasts on shortwave and mediumwave. However, SR International will retain German for a basic service of news on the Web and as a Monday to Friday podcast.
 

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WASHINGTON BEAT

Capitol Hill And FCC Actions Affecting Communications

by Richard Fisher, KI6SN

 

Survey Shows Natural Disasters Rank As Communicators’ Top Concern

Sixty-five percent of 200 public safety officials and first responders cited the ability to respond to natural disasters as their top concern in a nationwide survey conducted jointly by the Association of Public-Safety Communications Officials and Motorola. It dwarfed other concerns, which included “drug related crimes” (11 percent), “non-drug related crimes” (10 percent), and “terrorist attacks” (7 percent).
The survey also revealed that regarding “interest in new technology,” 47 percent of those surveyed have interest in “satellite tracking technology,” followed by “automatic license plate recognition” (41 percent), and “facial recognition technology” (37 percent).
In the area designated “importance of communications technology,” the survey found that “the importance of technology specific to communication is underscored by the officials’ funding priorities. Given a hypothetical funding increase for their departments, public safety officials on average would spend more of the money on communication technology [than] on additional training, and nearly as much as on additional personnel.” “Additional first responders” ranked greatest with 29 percent, followed by “communications technology” (27 percent), “first responder training” (25 percent), and “computer equipment” (18 percent).
“While better communications was the popular choice (19 percent) as the greatest benefit of advanced technology, it was also seen as the area in greatest need of improvement, cited by 30 percent of respondents,” officials said. “Our whole police department is dependent on wireless communications with laptops. We wouldn’t be able to operate if it wasn’t for that,” said Mike Helms, Director of Sports Services and Police Technology for West Melbourne, Florida.
APCO and Motorola reported that the “survey included fire and police personnel, EMTs and government officials in urban, suburban, and rural areas, providing a snapshot of needs for a cross-section of America.”
The APCO website can be visited at www.apcointl.org/.

FCC Questions California Radio Amateur’s Character

A California radio amateur has been issued a Hearing Designation Order by the FCC “to determine if his application for renewal of his amateur radio license should be granted.” William F. Crowell, W6WBJ, of Diamond Springs, is alleged to have “apparently willfully and repeatedly engaged in and continues to engage in unlawful Commission-related activities, including, but not limited to, intentionally causing interference and/or interruption, transmitting music and one-way communications, and using indecent language on amateur frequencies.” Crowell previously held the callsign N6AYJ.
 

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Monitoring Activity Along The U.S./Mexican Border

There’s Heightened Concern About International Boundaries,
Especially On Our Southern One—And You Can Listen In

by Mitch Gill, NA7US

 

For a country the size of the United States, the task of effectively monitoring the borders has always been formidable, but it has taken on a new urgency as terrorism and illegal immigration have become a top priority for our nation. Because of that, the activity level along the borders, especially the one shared with Mexico, has escalated as U.S. Bureau of Customs and Border Protection (CBP) officers and agents attempt to prevent illegal aliens, drug smugglers, and terrorists from crossing into the United States.

Communications, naturally, plays a huge role in their efforts to keep us safe. For the hobbyist, this means an even greater chance to catch some of the action. Patience and perseverance are key here, because the CBP, like most agencies, is moving toward secure communications. But don’t worry, there are still ample opportunities to listen in on frequencies that are non-secure. We’ll present some frequencies to listen to, but first let’s look at a little history.

Borders Tighten

When our nation began, there was no concern about controlling the borders, and people freely flowed in and out from Canada and Mexico. In terms of immigration, at least, international boundaries barely existed.

That openness changed dramatically in 1882 with the Chinese Exclusion Act. At that time in our history, many people believed that the legal immigration of inexpensive Chinese labor was taking jobs away from Americans. In response, Congress decided to limit immigration, reducing it to a fraction of what it had been. This led to immigrants crossing into the country illegally, creating the need for border security.

It was not until 1904, however, when inspectors, usually referred to as “mounted guards,” began patrolling the border from Texas to California. With only about 75 inspectors, this effort’s effectiveness was limited. In March 1915, Congress officially authorized the inspectors. Their primary job was to stem the flow of illegal Chinese immigrants, but they were also tasked with stopping all illegal aliens, as well as drugs, from reaching our borders. At times the military and the Texas Rangers were called in to assist. Their efforts were somewhat more effective.

On May 28, 1924, the Border Patrol was founded under the Department of Labor. Its mission was to prevent illegal entries into the United States along the Mexican border. In 1925 that mission expanded to include patrolling our coastline, and the Border Patrol increased to 450 officers.

Between 1932 and the end of WWII the service burgeoned to about 1,400 agents, who watched the Mexican and Canadian land borders as well as the coasts. During the war, agents provided even tighter control of the borders, assisting the U.S. Coast Guard in searching for saboteurs and also manning alien detention camps. Around that time, aircraft became an important tool of the monitoring operations, as did radio communications.

By the late 1950s private aircraft were being used to smuggle in illegal aliens, and with the assistance of other federal agencies, the Border Patrol began monitoring flights into the country in an effort to stem the tide. During the Kennedy administration, aircraft hijackings entered the news, and the President ordered the Border Patrol to provide agents to fly with domestic flights as a preventative measure.

The 1980s and 1990s saw a huge surge in illegal immigration. To meet the challenge, the Border Patrol quickly increased its manpower and began implementing more modern technology, including night vision goggles, upgraded computers, seismic sensors, and more effective radio equipment. Radio repeaters were placed on high hills to increase the range of handheld radios from five to 10 miles up to 100 miles.

In 1993, in an effort to gain more control of the border, operation “Hold the Line” was initiated in El Paso, Texas. Thanks in part to the new technological tools, Hold the Line was so successful that a similar measure, called “Gatekeeper,” was put in place on the San Diego border, where half the illegal entries were occurring. Within a few years illegal immigration was reduced by 75 percent in many areas and a national strategic plan was formed. As the borders became more controllable, agents were able to concentrate more on anti-smuggling and search and rescue efforts, such as BORSTAR (Border Patrol Search, Trauma, and Rescue).
 

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Revolution, Radio, And Border Guards Of Long Ago

During The Mexican Revolution, Radio Interceptors Helped Protect Our National Interests

by R.B. Sturtevant, AD7IL

 

Back in 1911 a fellow named Porfirio Diaz was worried about his job performance reports. He’d held his job, Dictator of Mexico, since 1876. Well, actually he’d run for president twice and been beaten twice, then he just took over. He’d done a lot of good for the country by building roads, railroads, and telegraph systems. He’d also saved a lot of time and money by doing away with the expenses and tedium of elections and a judicial system.

He had avoided political opposition by repressive use of the military and secret agents who divided the people into smaller and smaller political groups. But people were getting tired of all this oppressive government, and some muttered that Porfirio might want to retire. Porfirio knew that one of the ceremonies for retiring heads of the Mexican government often involved a stone wall and a 21 gun salute, fired just south of the collarbone. Porfirio, instead, decided to take a trip out of the country, work on his memoirs, and continue breathing.

The power vacuum created when Porfirio left was filled soon enough by Francisco Madero, a reformer with wide political support. Madero took over the Presidency in 1911 but almost immediately had a falling out with most of his major supporters. He was assassinated in 1912. So much for wide political support.

This new power vacuum left Mexico torn between four major groups. One was headed by Emiliano Zapata, who favored land reform; one by General Victoriano Huerta, a professional military officer who favored a military dictatorship; another by Venustiano Carranza, a strong Constitutionalist; and the last by Pancho Villa, who had the northern bandit vote locked up. Soon, more groups formed or broke off, leaving Mexico with quite a civil war on its hands.

Turmoil On The Border

Meanwhile, in Europe, Kaiser Wilhelm was planning some military adventures of his own. He’d “helped out” with things in Latin America, sending “advisors,” money, and weapons to assist Spain in the Spanish American War and saw no reason Germany should stop. Kaiser Bill had some plans of his own and wanted America occupied while he played takeover in Europe. So a large number of German “Reserve Officers” were dispatched to Mexico to attach themselves to the different revolutionary groups. Each group was separately wooed as the “Hope of the New Mexico” and promised funds, weapons, and advisors.

The Germans’ aim was to create unrest on America’s southern border to keep the country out of European affairs. Border incidents were staged to show the Americanos just how vulnerable they were. American interests in Mexico were threatened or seized, Pancho Villa raided Columbus, New Mexico, in March 1915, and five American soldiers were killed in Nogales by Mexican troops in 1918.

The Germans didn’t really care who ran things in Mexico as long as the Americans were kept busy. In 1915, the guy who was running things, more or less, in Mexico was Carranza.


Carranza represented the educated and politically powerful interests who wanted a strong Constitution. He also wanted Mexico to have a place on the world stage. He was listening coyly to what the Germans were saying while making his own plans. It was to Carranza that the famous Zimmerman Telegram was sent offering German assistance in a Mexican invasion of the United States. It was also to the Carranza government that Germany’s powerful transmitters aimed coded diplomatic traffic. Mexico, lacking such powerful transmitters, sent back messages that were picked up by U-boats in the Gulf of Mexico for retransmission.
 

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THE POP’COMM TRIVIA CORNER

Radio Fun And Going Back In Time

by R.B. Sturtevant, AD7IL

 

Q. What were some of the best jobs for radio operators on ships at sea?

A. In the 1960s the primo job for a ham radio operator was being the guy who ran the Radio Shack on the USS Hope, the hospital ship that traveled all over the world teaching local medical professionals the latest and greatest in new techniques and procedures. Typically, local telephones from foreign countries were costly and undependable, and the ship’s staff of around 140 could only contact home via amateur shortwave bands. When the ship’s station hit the air there was always an answer. And the radio operator was paid the same as the doctors and nurses—food, housing, and transportation. Everyone aboard the Hope was a volunteer.

Q. Did Radio play any part in sinking the Bismarck?

A. The problem with finding one ship, even the largest ship afloat, in a large ocean is that there are so many places to hide. But radio direction finding was turning into a major effort in the search for Hitler’s battleships, which were sent out to control shipping across the Atlantic. On May 1, 1941, the Bismarck put out to sea. She was found later that same month and attacked by the British Navy, but the battle ended with the Germans sinking the British battle cruiser Hood and damaging the battleship Prince of Wales. The question now was could the Bismarck be sunk?

Not seriously wounded during the engagement, the Bismarck did however suffer an oil leak and was losing fuel. Radio intercept work and code breaking soon told the British where their quarry was headed. On May 26 an obsolete Swordfish torpedo plane dropped a torpedo and crippled the Bismarck by destroying her rudders. The torpedo, really a near miss, caused the Bismarck to steam in a circle. The Germans soon ran out of ammunition and were
sunk by repeated attacks by British air and naval forces.

While the planes, torpedoes, and gunnery involved sank the Bismarck, it was the skill of radio operators that found her and kept her in their sights until she could be sunk. The Bismarck’s last message was also picked up by British intercept operators: it was, “Torpedo hit right aft. Ship unmanageable. We fight to the last shell. Long live the Fuhrer.” The famed German vessel went under on May 27.

Q. What was it like to be a ham in the Soviet Union during the Cold War?

A. In 1965 an American ham working for the U.S. Information Agency visited the Soviet Union to help show off American consumer electronics. His particular job was to operate an American-style ham shack and talk to Soviet hams. He met about 2,000 hams and visited many of their shacks. He found that most of them were using military surplus receivers of fairly recent vintage, but that the transmitters, antennas, and keys were all homebrew. The transmitters could operate CW or phone, and many had SSB capability. Training was available widely but the exams were oral and not standardized across the country.

Apparently, the biggest problem Soviet hams faced was television interference. This was because Soviet TVs were built without high-pass filters. Unless a ham could prove that his rig was TVI-free he could not operate after 6 p.m. weekdays or after noon on Sunday until midnight, when the TV stations went off the air.
 

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Cuba Si, Castro No!

With The Fate Of The Caribbean Nation Uncertain, The Waning Days Of
The Castro Regime May Be Your Last Chance To Log A Bit Of History

By Gerry L. Dexter

Might you be in the market for a circa-1950 automobile to show off at classic car rallies? If so, you could probably pick one up for a song from a Cuban cab driver, ’cause old Fords and Chevys are the limping motorized transport around decaying Havana.

Although set to some fabulous music, daily life in Cuba is an unhappy challenge. If you’re lucky enough to have a job you can’t change it without government approval. The much-touted free medical system lacks everything but patients, which it can’t treat anyway. Just about every facet of life in Cuba today could be described as old, decrepit, forlorn, bereft, desolate, and any of a half dozen other negatives you care to toss in. That applies even—or especially—to Fidel Castro.

Every week or so new rumors of his imminent departure to his reward take wing around Miami and other Cuban population centers in the U.S. So far (as of this writing), they’ve been false alarms. The 82-year old Commandante, has been trying to recapture his health for going on two years now and recently did the heretofore unthinkable: he stepped down as Cuba’s “president” in favor of brother Raul. And smiles were seen all along Interstate 95. (Of course, by the time these words reach print, events may have already unfolded dramatically!)

As his declining health could no longer be ignored, a couple of years ago Castro turned most responsibilities over to his then-77-year old brother. Some find slight hope for the future in this, believing that Raul is more pragmatic and reasonable than his older brother. This view holds that Cuba might one day take up the China model; that is, retain an authoritarian regime but don a capitalist coat, as Beijing has done. Others say that Raul is just another murderer who will keep the guns loaded and the padlocks on. Other analysts suggest a military coup might be in the offing. Obviously, no one really knows for certain, and in the meantime the Miami exile community waits expectantly, and hopes for the best.

Radio In Cuba, Then…

Radio has certainly had its role in the unending campaign to oust, or at least subvert, the brothers Castro. During the Cuban revolution the Castro forces used a 120-watt amateur transmitter to get their Radio Rebelde on the air. Once the revolutionaries took power the radio station was made legitimate and today is the “other” Cuban shortwave broadcaster, after Radio Havana.

In the early 1960s, as part of the lead up to the Bay of Pigs invasion, we had the infamous CIA-run Radio Swan (later Americas) broadcasting to Cuba from Swan Island. It was later joined by Radio Libertad, “La Voz Anti-Communista de America”—also of suspect parentage—which was eventually found to be broadcasting from a highly secured installation near Caracas, Venezuela. (Today’s Hugo Chavez regime probably wouldn’t care to be reminded of that historical embarrassment.)

By the early 1980s there were several anti-Castro broadcasters of a more or less amateur nature operating sporadically in the lower part of 7 MHz. Radio Abdala, La Voz de Alpha 66, Radio Antorcha Martiana (Torch of Marti) and others would appear and disappear without any discernable pattern. The groups or individuals sponsoring these broadcasts had occasional run-ins with the local authorities and were not above resorting to violence when they believed it would advance their cause. Those were exciting times to be a shortwave clandestine chaser!
 

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 Must-Have Software And Websites For
The Radio Hobbyist’s Computer

These Recommended Tools Will Help You Get Even More Out Of Listening In

by Dan Srebnick, K2DLS

 

Computers and radio work well together—or do they? Most of us have probably spent time trying to figure out why some piece of computer equipment in the shack is causing QRM to our favorite frequency. I’ve gone so far as to power off every computer in the house in order to bring the noise level down a couple of S units and pull out that rare DX station. I’ve used lots of ferrite chokes and even changed PC power supplies to eliminate RF hash caused by some switching power supplies in computers.
It can be annoying, to say the least, but I can’t imagine not having a computer in the shack these days. There are just too many useful software programs and websites that enhance my listening pleasure. Computer noise suppression in the shack is a science unto itself, but we’ll talk about that some other time. Today, we’re going to talk about some of those programs and websites that support your hobby habit.

Tech Tools You Don’t Want To Be Without

A lot of hams and SWLs bemoan the absence of sunspots, proclaiming the bands dead for the next couple of years. I’m not so certain I agree with the part about the bands being dead, but conditions certainly have been challenging on the shortwaves. What seems to be true, however, is that the activity moves lower in frequency the quieter the sun gets. While much has been written about the 11-year sunspot cycle and its effect on radio communication on HF, a picture is worth and thousand words and I have the picture, thanks to www.spaceweather.com (see Figure 1).

Website: www.spaceweather.com

This is a terrific website. I look at it daily, mostly to see at a glance whether there’s hope of decent propagation on the higher frequencies. In the left hand column, there is a vivid image of the sun, showing any sunspots, or the lack thereof, with the current sunspot number. There’s a good explanation of how the sunspot number is derived that you can access by clicking on the link under the current number. Readers contribute photos of interesting occurrences, such as unique auroral conditions visible at their locations. Other useful information presented on the site includes dates of upcoming meteor showers, in case you’d like to work some meteor scatter using the weak signal software from WSJT.

Software: VOACAP and VOAProp

One great program that will help you figure out what you can hear and when is VOAProp (www.g4ilo.com/voaprop. html). VOAProp was written by Julian Moss, G4ILO, and has often come up in the pages of Pop’Comm. It makes use of the VOACAP propagation prediction library, but puts a nice graphical interface on top of it. It has a mode for SWLs and one for hams, with the main difference being the transmitter power levels and bands for each community of users. The GUI (graphical user interface) also clearly shows the grayline at any given time, revealing opportunities for extraordinary DX conditions. The software runs under both Windows and Linux, and ran just fine under Vista. The required VOACAP program can also be downloaded by the VOAProp installation program. If this sounds a little complicated, it really isn’t and the end result is well worth it.
 

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GLOBAL INFORMATION GUIDE

VOA To Get A Facelift, Plus Other Tweakings

by Gerry L. Dexter
 

We have several times now bemoaned the seeming disinclination of the Voice of America to put much time or effort or funds into its declining broadcast infrastructure. Evidence of said: the closing of the Bethany (Ohio) site several years ago and, more recently, the Dixon (California) facility, followed by turning over the Briech, Morocco, site to the government there, not to mention the lack of attention given the giant Greenville (North Carolina) facility, which is beginning to show its age. But now there has been a bit of a turnabout.

The VOA has awarded a large contract to the Harris Corporation to modernize the Voice’s broadcast headquarters, an undertaking that will include new automation, new master and quality control, and updating playback and recording systems. In reality, the headquarters upgrade likely has no bearing on what’s going on at tower sites, but it’s still tempting to hope that, maybe, this indicates the start of a new way of thinking.

The VOA has also announced that its “Radio Aap Ki Duniya” Urdu service has ended shortwave transmissions and now uses only two channels on mediumwave. It seems like only a year or so ago that this service went on the air in response to some perceived urgent need.

Somebody keeps tossing the BBC into the wrong wash cycle—it’s shrunk again!

BBC shortwave to Europe is no more. What’s next? America? Oh wait—I seem to remember there was something in the paper a couple of years back about that…
Now there are rumors—not much more than simple scuttlebutt at this point—that Radio Tirana may be discontinuing shortwave before long in favor of “broadcasts” on the Web, which are much cheaper. Let’s hope that doesn’t happen. As always I suggest writing to the station to show your support. The snail mail address is Ruga Ismail Qemali No. 11, Tirana, or you can email them at radiotirana-english@hotmail.com.

Radio Prague is once again being relayed over WRMI-Miami, for a full half-hour per week! It airs Saturdays at 0000 on 9955.

Israel was all set to pull the plug on its shortwave broadcasts effective with the arrival of the New Year. But, once again, the programs were granted a three-month delay. It’s anyone’s guess as to what their status may be as you read this.

Radio Ukraine International is active again from the site at Lvov, using 7440 at 0000 to 0100 in Ukrainian and 0400 to 0500 in English.
That’s it for this month’s shortwave gazette—now it’s over to you.

Reader Logs

Remember, your shortwave broadcast station logs are always welcome. But please be sure to double or triple space between the items, list each logging by the station’s home country, and include your last name and state abbreviation after each. Also needed are spare QSLs or good copies you don’t need returned, station schedules, brochures, pennants, station photos, and anything else you think would be of interest. And how about sending a photo of you at your listening post? It’s your turn to grace these pages!

Here are this month’s logs. All times are in UTC. Double capital letters are language abbreviations (SS = Spanish, RR = Russian, AA = Arabic, etc.). If no language is mentioned English (EE) is assumed.

ALASKA—KNLS, 7355 opening in CC heard at 1400. (Barton, AZ)

ALBANIA—Radio Tirana, 6120 at 0245 and 7425 announcing times and frequencies at 0440, (Maxant, WV) 9915-Shijak at 2115 and 13640-Shijak at 1540. (Charlton, ON)

ALGERIA—RT Algerienne, 12025 via England in AA at 2015. (Brossell, WI)

ANGOLA—Radio Nacional, 4950 at 0140 with PP talk and mostly Portuguese pops. (Alexander, PA)

ARGENTINA—Radiodifusora Argentina al Exterior, 15345 in SS at 1810. (Maxant, WV) 2248. (Wood, TN)

 

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SCANTECH

Scanner Systems

by Ken Reiss

 

As the technology involved becomes more complicated, scanner listeners are faced with a need to understand trunking, digital, and a whole lot of other radio systems. If you’re new to scanning, this can be somewhat daunting as it’s a lot of information to process all at once, and in some cases, until you understand all of it, your scanner won’t work correctly. Let’s see if we can demystify some of the technology and help you understand why it works the way it does (when it does work).

“Conventional” Radio

We’re all familiar with the concept of channels. If you want to watch TV you tune to a certain channel; to listen to the radio you tune to a favorite station’s “channel,” or frequency, to listen to it. The difference is that these channels are used for broadcasting continuous programming, while two-way radio systems are used as needed, but there are channels involved here, too.

You don’t need to know, or care, what actual frequencies TV Channel 7 is on, you just know that the news is on at 6. Two way-radio systems don’t have such convenient schedules, but the users of those systems don’t really care what actual frequency they’re on, either...they just need to know that Channel 3 on their radio is the dispatcher for their district and Channel 8 is the car-to-car channel for getting doughnuts. Keep that in mind for a few minutes while we discuss less sophisticated radio systems.

The so-called conventional radio systems (conventional because it represents the old way?) are just like the TV channels. Each channel is assigned a fixed frequency, and all the traffic for that channel takes place on that frequency. The limits are how many channels you have available versus what kind of divisions the users of the system need. You may not care if they’re all on the same channel if there’s only a few, but things get pretty crowded if you’ve got a large city on a single channel, as New Orleans found out not so long ago.

I’m certain that if you’ve owned a scanner for more than five minutes, you probably have a pretty good handle on how conventional radio systems work. Each channel has a dedicated frequency (or two) for its use and no other traffic takes place on that channel. If a car needs to talk to some other unit, there’s a channel switch on the car radio and that’s a different frequency, much like the TV channel idea.

Single frequency operation is the simplest form of this and is referred to as simplex. Only one person can talk at a time and the other units (and your scanner) can only hear that person, or car, or whatever talking if they are close enough for the signal to reach there. Simplex is cheap and easy. In a simplex system, both sides transmit and receive on the same frequency. This is the simplest type of radio system and one that is used in many places throughout the country because of that.

Unfortunately, if the area to be covered is large, then some of the mobile units won’t be able to hear each other, and that can be the cause of some safety concerns and can make operation difficult if the dispatcher has to constantly relay things. If two units that can’t hear each other transmit at the same time, the dispatcher may not hear anything but garble. If a mobile unit transmits close to another mobile unit, the second unit may not hear the dispatcher in the mess. The solution to that was to put the mobiles on one frequency and the base station on another. At least the dispatcher would always have a clear channel to talk on and the mobiles could hear. That solved half the problem.
 

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POWER UP: RADIOS & HIGH-TECH GEAR

New, Interesting, And Useful Communications Products

 

Trackstick Personal GPS Tracker

With the summer travel season approaching, vacationers may want to check out the Trackstick II Personal GPS Tracker from Trackstick.com. The Trackstick records its own location, time, date, speed, heading, and altitude at preset intervals and, with over 1Mb of memory in a waterproof package, it can store months of travel information. Use it to keep track of the exact routes you take when hiking, biking, or any other activity and record the location of everywhere you travel—you can even import pictures and other information into Google Earth. A GPX photo-stamping feature lets you add photos to your own maps.

The Trackstick II receives signals from 24 satellites orbiting the Earth and uses them to precisely calculate its own position anywhere to an accuracy of within 45 feet. Other applications include photo tours, public safety, homeland security, law enforcement, and child safety.

Trackstick II is available through numerous sources and can be found online for under $200. For more information visit www.trackstick.com.


CableOrganizer.com Offers “Green” Gadgets

Consumers who want to save the planet—and some bucks along with it—have a couple of offerings available to them through CableOrganizer.com.

The company’s Watts Up? electricity meter provides a convenient way to monitor and project energy costs by measuring what standard 120-VAC electrical devices will cost to operate, eliminating the guesswork involved in the price of powering a piece of equipment over a short or long span of time. The meter quickly displays the wattage and the electrical usage cost (16 electrical measurements and values are offered). The Watts Up? meter will also help identify operational problems, measure line voltage, and diagnose voltage drops. Included PC software allows memory to be downloaded into charts and tables.

Another cost-saving gadget, the Kill A Watt power monitor, also provides an economical way to assess the efficiency of your electrical appliances. Just plug any 115-volt (maximum 15 Amp) electric appliance into the Kill A Watt meter and its large LCD display shows the power consumption of the appliance in killowatt-hours. The Kill A Watt power monitor can calculate the electricity cost of the appliance by the day, week, month, or year. If your electric bills are high, the Kill A Watt power meter can help you pinpoint which electric appliances are consuming too much power and can monitor the quality of your power by checking voltage, line frequency, and power factor.
For more information on the Watts Up? ($72.95–$195.95) and Kill A Watt ($29.95) meters, visit http://cableorganizer.com.

 

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BROADCAST TECHNOLOGY

The Ultralight DX Phenomenon

by Bruce A. Conti

 

First there were crystal radios, then one-tube sets, and now there are “ultralights.” Sparked by the popularity of the Sony SRF-59 AM/FM Walkman, a very capable retrograde pocket radio, ultralight DXing has ignited an explosion of experimentation and interest in radio electronics. In this digital age of endless entertainment options, including cable TV, the Internet, and wireless phones, the rapid growth of ultralighting is quite remarkable.

Ultralight Defined

“The sudden boom in ultralight radio interest took everybody by surprise, and the AM DX community is only now trying to sort out the definitions, and create some guidelines about this new phenomena,” said Gary DeBock, a Washington State DXer and ultralight enthusiast, in response to my inquiries about the subject. “We are still attempting to create an administrative framework that will give support and direction to the enthusiasts in this new niche of the AM DX hobby, and not every decision will be without controversy.” DeBock continued:

DXpedition enthusiasts in particular are already creating a lively forum of discussion about how these tiny receivers should be used, and what should be allowed. This is healthy, in my humble opinion. We have very serious experimentation currently with antenna transplants into ultralight radios, and one of my own projects transplanted a 6.25-inch loopstick from a Sony ICF-S5 into an SRF-39FP ultralight, resulting in a huge boost in sensitivity. It certainly isn’t a stock ultralight, but is it on a different DXing level than the Sony ICF-2010, for example? What if we transplant an even bigger antenna into an ultralight radio, along with filter mods and other refinements, making it a DXpedition superstar...would it still be an ultralight? Whether we agree on this or not, that is the direction that Guy Atkins, John Bryant, and myself are inclined to go.

World-renowned mediumwave DXers Atkins and Bryant are two co-conspirators at the forefront of the ultralight movement. Though not an ultralight, the Sony ICF-2010 is a classic portable communications receiver best known for its unparalleled AM synchronous detection circuitry. The 2010 was discontinued in 2003, yet it’s still the reference for comparison of portables to date.
Regarding ultralight experiments, DeBock said:

The “hot-rodded” SRF-39FP already has sensitivity at least up to the ICF-2010 level, but it is analog and obviously will not be the first choice of DXpeditioners. We plan to modify a Sangean DT-200VX to make it a super-sensitive, super-selective digital wonder, but if we succeed in this, some will obviously question what kind of animal we have created, and whether it is really an ultralight. Since there is no judge that can satisfy everybody, the current scramble seems to be in the direction of making these tiny radios as competitive as possible for DXpeditions, and letting the AM DX community sort out the definition concepts later.

The Sangean DT-200VX, like the SRF-39, SRF-59L and others in the Sony Walkman lineup, has quickly gained superstar status among ultralight DXers. The “P” version of the SRF-39 was manufactured with a clear plastic chassis for prisoner use. The clear chassis allowed easy inspection for contraband by prison security.

Ultralight Classifications

What is ultralight DXing? In its most basic form, ultralighting is done with a pocket radio reminiscent of the classic transistor radios from years gone by. Consider it an upgrade from the good old days of DXing with oatmeal-box crystal radios, a back-to-nature minimalist movement for radio hobbyists, and for some simply a rekindled youth.
 

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THE ANTENNA ROOM

Using SWL Diversity Antennas

by Kent Britain, WA5VJB

 

Ahhh, ever since those early days when I spent a month’s allowance for an old shortwave radio at a garage sale, I’ve had a soft spot in my heart for them. These days I have about two dozen radios with at least one shortwave band around the house.

Today I most enjoy prowling the shortwave bands with my Racal RA6790 (Photo A). Note to Readers: If you have any experience working on these, drop me an email, mine has picked up an annoying habit. To enhance my listening experience, I’ve found that a DSP filter is a handy addition, and external speakers also improve the sound. (As a quick aside, I used 4-Ohm speakers, so I just wired them in series to get 8 Ohms. When you parallel or series speakers watch that +/- on the speaker phasing. If the cone on one is going out while the cone of the other is pulling back, the sound is pretty strange. This is a phase condition that just doesn’t occur in nature over a range of frequencies, so the human ear finds it sort of annoying.)

I guess my second favorite has to be the RadioShack DX-394 (Photo B) since I have three of them around the house. If you can work with surface mount components, there are several simple modifications that improve the background noise and AGC functions on the DX-394; a simple Internet search will turn up these modifications so I won’t list them here. Again, an external speaker sounds much smoother than that little internal speaker. And you can add one of those noise canceling or DSP audio processors as well. The DX-394 also works well on an external battery pack, which is very nice in my area since we have far-too-frequent power failures.

Now, The Antennas

Most of the time I have a ground-mounted vertical with 300-plus buried radials connected to my Racal. But I also have two other antennas I can switch in: a 20-foot wire in the attic that I often find works better than the big one out back, and an active antenna (but we covered those just a few months ago).
When the shortwave signals bounce between a couple of ionization layers several times, the angle and polarization of those waves can get pretty mixed up. So it can get hard to predict what kind of antenna will work best. A simple solution is shown in the accompanying Figure—just have several antennas and use the one that “hears” best.
Photo C shows a coax type-N, TV antenna, TV video, and an audio switch box. All of these switch boxes work fine for switching shortwave antennas. You don’t need special coax relays just to switch between a few long-wire antennas. Many of the TV and cable-type antenna/coax switches use type-F connectors. Type Fs work great on shortwave, and the 75-Ohm connectors and cables have very low loss on these frequencies. Even video switches work fine for switching your shortwave antennas. HeathKit used to use RCA plugs as high as 148 MHz, those RCA plugs, switches and cables are fine on shortwave and up to 30 MHz. A good video switch must have an excellent SWR to over 6 MHz to carry video without ghosts.

It’s certainly easy enough to build your own antenna switch with toggle switches or most any multipole switch. But if you don’t like to roll your own, a CATV A-B switch, the DVD/VHS/converter video switch, or even a speaker selection switch can be used for your shortwave antennas; the frequencies are low, power levels are low, and impedances are not critical. Let me know how you make out.

From Our Readers

There were a few comments/questions from our readers that I’d like to share this month. One was on the topic of measurements, specifically, mHz, kHz, MHz, and GHz. Let’s do a quick review.
 

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PLANE SENSE

The ABCs Of Scanning The Skies

by Tom Swisher, WA8PYR

 

So you’ve decided to give aviation monitoring a try and have tracked down sites on the Internet loaded with aviation frequencies. Did you find yourself a bit vexed looking at those aviation frequency listings and wondering what all those abbreviations mean? I’m betting you did, so I’m going to use my first column to address that right away. We’ll also go over the meaning of classes and look at just what there is to hear out there. In other words, the basics.

Sites like Airnav.com have excellent frequency listings for airports all over, but they refer to frequencies and other aspects of airport operation with some pretty esoteric abbreviations. You’ve probably said to yourself, “Abbreviations? Those aren’t abbreviations? They’re code!!!” And in many ways, you’re right. Many of these abbreviations were developed in the mid-20th Century, and at the time (and for many years after) the primary means of communication was via teletype. With bandwidth on the wires being a limited resource, a message had to be gotten across quickly and in a way that was easy to understand. Thus, a variety of abbreviations or acronyms was developed to save bandwidth yet still get the message across. Although teletype is rarely, if ever, used today, the abbreviations and acronyms have persisted. It doesn’t make it easy for newcomers to aviation monitoring to figure out what they’re listening to, though.

To help you along the road to peace, love, and understanding, we’ve provided a basic primer of abbreviations and their meanings (see “Common Aviation Abbreviations”).

Aviation Classes

Another listing given for airports is the airspace class; this is given as CLASS (x), where X is a letter, A through G. This refers to and gives the frequencies for controlled airspace at that particular airport. Each airspace classification carries various requirements for how an aircraft must be equipped and how flight operations are carried out. The classes are as follows:

Class A—Airspace above 18,000 feet. All flight conducted using IFR or SVFR, with clearance from ATC. All flights separated by ATC.

Class B—Flight conducted using IFR, SVFR, or VFR, with clearance from ATC. All flights separated by ATC.

Class C—Flight conducted using IFR, SVFR, or VFR, with clearance from ATC. IFR and SVFR flights separated by ATC; VFR flights maintain separation from other VFR flights with verbal information from ATC.

Class D—Same as Class C, except VFR flights maintain separation from all other aircraft with verbal information from ATC. All aircraft are given information on position of other aircraft.

Class E—Same as Class D, except VFR aircraft are not subject to ATC clearance. All controlled aircraft are given information on position of other aircraft when possible.
 

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HAM DISCOVERIES

PSK31: RTTY’s Replacement Is All Grown Up!

by Kirk Kleinschmidt, NTØZ

 

I’m sure people of every successive generation have rolled their eyes and wondered mightily about “the youth of the day.” For example, instead of walking to and from school in Arctic blizzards, torrential downpours, and searing heat (yes, with buzzards circling overhead), today’s kids are driven to school in fleets of armored SUVs helmed by soccer moms gone wild.

And while kids in my generation went outside in the morning and reluctantly came indoors as late as possible (getting into ever-increasing mischief the whole while), today’s kids can barely tear themselves away from whatever game console is the rage. And when they do manage to go outside, they’re limited by the “carpal thumb” syndrome caused by chronically mashing buttons on said console’s handheld controllers.

The same generational transitions happen in ham radio, too. Spark gave way to continuous wave, AM to SSB, etc. And nowadays, radioteletype, RTTY, the original two-tone keyboard-to-keyboard mode, has largely given way to PSK31, the now-preferred keyboard-to-keyboard mode, which will be 10 years old at the end of this year.

Although spark transmissions are now understandably verboten, I know that hams still have occasional AM QSOs and that RTTY isn’t completely six feet under—especially for digital-mode contesters—but it has one foot in the grave. And the equipment we use for RTTY, well, it’s a whole new ball game. A computer ball game (more on that later).

We’ve come a long way from the clunky teleprinter machines used by early RTTY ops. Even if you haven’t seen the gear I’m talking about in a ham shack, you’ve undoubtedly seen it in older movies about war or broadcasting! Behind a typewriter-looking keyboard sat a teleprinter with a large continuous roll of low-grade yellow paper. As the receiver’s analog demodulator converted the deedle-eedle tones into readable characters, those characters were impact-printed onto the paper, making a lot of clattering, clunking, whirring, and clicking noises in the process.

As RTTY hardware improved in the ’70s and ’80s, hams and SWLs started monitoring shortwave RTTY and fax stations with a variety of equipment, ranging from cheap two-diode PC serial interfaces to expensive HAL or Universal terminal units.

In the late ’80s, multimode terminal units from Kantronics and AEA (often dubbed multimode communications processors, or MCPs, which were used with PCs or “dumb” terminals) were the rage, pushing aside even the more robust RTTY-only gear made by companies such as TONO and HAL.

During this time, RTTY itself saw competition from the various error-correcting “handshaking” modes—AMTOR, packet, PACTOR, G-TOR, CLOVER, and so on—and I wondered even then whether the RTTY era was coming to an end. RTTY was still around then, just like it’s still around today, but it wasn’t exactly the “in” thing unless you were a ham radio digital-mode contester (still true today, only to a greater degree).
 

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THE PROPAGATION CORNER

Two Different Predictions For Solar Cycle 24

by Tomas Hood, NW7US
 

You may not have noticed it, but recently certain propagation prediction and modeling software programs (for instance, ACE-HF) that attempted to obtain the smoothed sunspot number (SSN) for future dates, no longer were able to complete that function. This occurred on January 1, 2008, because of the government’s failure to issue updated predictions for solar cycle activity for 2008 and beyond.

The National Geophysical Data Center (NGDC), a part of the National Oceanic & Atmospheric Administration (NOAA) and other agencies, has now fixed its SSN listing, allowing the software functions to work again. This was prompted by the folks at ACE-HF, who also asked the NGDC to include data back through 1997 from their old table as well as estimates for Cycle 24, so ACE-HF can now retrieve SSNs from 1997 through 2018. Figure 1, by the way, is an attractive EIT (for Extreme ultraviolet Imaging Telescope) depiction of most of a solar cycle.

The government listing was delayed because of the difficulty in deciding on the month of the current solar cycle’s minimum, on which future months’ estimates are based. They have posted the following “readme” that qualifies the current estimates:

The sunspot prediction file is a PRELIMINARY look at Cycle 24. Our prediction program required the month and year of minimum to produce output. Solar minimum for Cycle 24 has not been officially determined. We used July 2007 as the minimum date to produce an outlook. Solar minimum will be adjusted monthly until the OFFICIAL value/month is determined.

Another interesting turn of events regarding the prediction of Solar Cycle 24 is this statement released by the International Solar Energy Society (ISES) regarding the Solar Cycle Progression and Prediction Displays (see Figures 2 and 3):

The initial ISES Solar Cycle 24 Prediction was released in April, 2007. The panel charged with determining the prediction was unable to agree on a single solution and have so far provided two predictions. Those two predictions are available here, along with an average of the two predictions. The average is currently being used as the official prediction. The ISES panel does not consider this to be an adequate solution. To mitigate this, the lower and upper bounds used with the average cover the range of the two predictions issued by the panel. When the panel converges on a single prediction, the files here will be updated to reflect the new prediction. The two predictions issued by the panel can be accessed in the files named Predict_low.txt and Predict_high.txt.

To view the latest predictions, including these two files, point your Internet browser to www.swpc.noaa.gov/SolarCycle/.

Scientists have issued cycle predictions only twice before. In 1989, a panel met to predict Cycle 22, which peaked that same year. In September 1996, scientists met again to predict Cycle 23, six months after the cycle had begun. Both groups did a better job at predicting timing than intensity, according to Space Environment Center scientist Douglas Biesecker, who chairs the current panel of experts that came up with last April’s (2007) prediction for Solar Cycle 24. He describes the group’s confidence level as “high” for its estimate of a March 2008 start month for the new cycle, and “moderate” overall for the two estimates of peak sunspot number and when those peaks would occur.

One major disagreement among the current panel members involves the importance of magnetic fields around the sun’s poles as Cycle 23 decays. Those who predict a weak Cycle 24 point to the end-cycle polar fields as the foundation of their forecasting approach. The strong-cycle forecasters place more importance on other precursors extending over a several-cycle history. Because Cycle 24 sunspots have already appeared this year (2008), the strong-cycle group holds that Cycle 24 will be a moderate to strong cycle.
No one will know for sure until we are well into the solar cycle. What’s more, scientists need at least one year of new solar cycle data to really create the curves that allow them to better forecast the rest of the cycle’s activity levels and the timing of the peak.

 

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RADIO RESOURCES

DSP Noise Reduction Speakers

by Gordon West, WB6NOA

 

 If you listen to your scanner and two-way radio system for hours on end, you can appreciate the external speaker jack for a big speaker. My ham rig’s original external speaker was a 12-volt DC-powered Variable Response Console from Alpha Delta Communications. The big speaker gave me rich audio, and I could power on the fully adjustable analog equalization network, giving me high boost, low boost, and a relatively decent null to reduce an annoying high-frequency heterodyne whistle. It even had a jack for headphones, allowing me to play with high and low boost knobs for just the right pitch, without driving everyone else in the radio room nuts!
Each of my scanners had a Motorola speaker box, which certainly gave a fuller, richer-sounding audio output than did the relatively small speakers in the scanners themselves.

When I added a similar-type GE speaker to my 2-meter/440-MHz ham set, things sounded fuller, but the rumble of repeater output CTCSS was a distraction. Even my big Alpha Delta VRS was not totally effective in rolling off the low CTCSS tones.

It Just Keeps Getting Better

This was 10 years ago, about the same time that SGC Corporation introduced a marine radio with Advanced Digital Signal Processing (ADSP) 12-volt powered noise subtraction system. It was big and bulky and the red, amber, and green LED bar graphs looked really “gee whiz” in my radio room.
Boy! Did the SGC ADSP audio noise subtraction system work well! On ham radio, it would take about five seconds to analyze the background noise, and then slowly reduce it to nearly zero. On the VHF/UHF sub-audible above 103.5 Hz, it would magically analyze the steady tone frequency and subtract it from the big speaker output. On my scanner, “basso profundo” dispatchers now had the same characteristic as a tenor, minimizing speaker rumble.
Soon, SGC was joined by other radio manufacturers employing an imported European Digital Signal Processing (DSP) chip that would perform near magic on audio signals coming out of your radio system.
The DSP would far outshine my analog high-pass and low-pass adjustable circuits in my earlier powered speaker system. With DSP filtering, broad analog response curves turn into steep digital walls for precise noise attack and specific frequency response.

Here’s How It Works

The audio out of your radio’s external speaker jack first enters the DSP speaker’s analog-to-digital (A/D) converter, then goes to the DSP ROM. It then goes out the processor’s RAM to the digital-to-analog (D/A) converter, then to a headphone or speaker jack or its own built-in speaker. Inside the DSP chip is a very-high-speed microprocessor that performs a routine called Multiply And Accumulate (MAC) in just one clock cycle. In most of the newer DSP speaker systems, all the software programming is automatic, leaving you with only a DSP level adjustment.
As analog audio enters the analog-to-digital stage inside the chip, a sample and hold circuit may sample both amplitude and specific frequency in time, executing millions of audio “slices” that are converted into binary numbers. While audio CD players must execute high sampling frequencies, human speech is much easier to quantify then a rock band!

 

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REACT IN ACTION

REACT Month Celebrates Much

by Ron McCracken, KG4CVL / WPZX486

 

“What’s with this ‘REACT Month?’ you may ask. Well, it arrives annually in May, just as people begin to think about travel for Memorial Day, the Fourth of July, weekend jaunts, and summer vacations. In the excitement of making plans, REACT Month reminds us of our need to plan for safety.

REACT Teams across the nation and around the world will host safety displays in public places and provide speakers on safety topics to community groups. Their goal is to help radio enthusiasts get the best from their radios in an emergency by learning correct distress call procedure.

Other REACT Teams will conduct neighborhood SOS Drills to help residents prepare for severe weather outbreaks or similar local emergencies.

Individual REACT volunteers will continue to monitor CB Channel 9 and FRS/GMRS Channel 1 for distress calls from travelers, boaters, hikers, and others.

Turnabout

REACT Month is also a time for Teams to celebrate the achievements of their volunteers. REACTers quickly realize their need for on-going training in order to be of maximum service to those in distress. Likewise, to assist local authorities effectively when needed, REACT personnel need to be familiar with the requirements of those agencies. During REACT Month REACT Teams will often recognize those who have helped train their members over the past year, too.

The Points of Light Foundation, established by former president George W. Bush, recently honoured two REACT members for their contributions. As is often the case, their community service extends beyond REACT. Each has received letters of congratulations from both the current President Bush and the former President Bush.
Sue Currie of Louisville Metro REACT (Kentucky) was one of the honorees. In addition to her REACT efforts, Sue serves with the Red Cross and the United Way. She was honored by the Red Cross with its Clara Barton Award in 2007.

Bill Kofron, Colleton County REACT (South Carolina) is another honoree. Bill rides with the Blue Knights law enforcement motorcycle club in one of his “other lives.” He also serves as chaplain to a VA hospital and the Fraternal Order of Police. He, too, helps the Red Cross as well as the Heart Association and other groups in addition to his REACT duties. He was named REACTer of the Year for 2007 by the South Carolina REACT Council.

Neil Jackman, REACT Nicholson (Mississippi), was recognized by REACT International, Inc., upon becoming only the second REACT volunteer so far to successfully complete the rigorous requirements of a REACT Certified Emergency Communicator. Each candidate must complete an advanced, in-depth REACT course in emergency communications. A candidate must then be evaluated during a real incident or major exercise in order to qualify for certification.

In other news, Tom Currie, Training Chairman for REACT International, Inc., has been appointed by the National Registry of Certified Emergency Communications Volunteers (NRCEV) to its Certification Board. Currie has been an amateur radio and CB operator for 30 years. He serves with Louisville Metro REACT and has held various offices with his Team and the Kentucky REACT Council. He has also represented REACT on the Kentucky Volunteer Organizations Active in Disasters (KyVOAD).
 

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THE WIRELESS CONNECTION

Measuring Receiver Sensitivity

by Peter J. Bertini

 

It’s often said a man is only as good as his tools. I think this is a wise adage, and I’m a sucker when it comes to buying the best test equipment I can afford! I love to experiment, and I enjoy dabbling in both vintage and modern electronic communications equipment. I also like to design and homebrew my own ham equipment. My work is only as good as my education and the equipment that backs that up. Both reinforce each other.

Fortunately, we live in good times. I am not a rich man, but there’s so much high-end lab-quality test equipment from industry and government sources being dumped on the surplus market. And as the supply often greatly exceeds the demand, the prices on desirable goodies frequently drop within reach of the meager assets in my very thin wallet.

There are some extreme bargains to be had! For instance, signal generators that cost tens of thousands of dollars 20 or 30 years ago are now available for a few hundred dollars. But the asking prices can vary greatly depending on where and how you shop. The best bargains are found at the bigger, well-attended ham fleamarkets. For example, if you can make the yearly pilgrimage to the Mecca of ham radio gatherings, the Dayton Hamvention, you’ll find deals galore in the large outdoor fleamarket. Remember few vendors want to haul all of that equipment back home! On the other hand, dealing on Internet auction sites means buying sight unseen, from professional resellers, and you’ll be bidding against a worldwide market to boot!

We’ve discussed RF signal generator basics in past columns. We’ve shown how to improve the utility of the Heath SG-8 signal generator, a basic low-cost instrument that was marketed to meet the needs of the most frugal radio enthusiast. Stepping up another notch in quality would encompass signal generators marketed for the radio and TV service industry. A brief list of manufacturers that catered to those markets would include familiar brands like Hickok, Simpson, Heath, Eico, RCA, and Precision. Many of these early generators are functional and in daily use to this day.

Based on the positive feedback from our past musings on restoring and using shop test equipment I think this might be a good time to delve further into the mysterious realm of signal generators. This column will need to be continued in a future issue, as there’s a lot of material to cover—but if you stay with me I promise you’ll learn a lot about using signal generators and how to make useful and accurate RF measurements!

Unfortunately, service shop-grade signal generators have limitations. While the output level is adjustable, the levels are relative and not calibrated. The modulation level might be adjustable, but the percentage of modulation isn’t known. The dials are analog, and the precision and scale accuracy are often less than what is needed. Precision means the degree to which the dial resolves your ability to set the generator to an exact frequency; for example, it’s possible to set the dial to the closest 10ths of kHz or kHz. Accuracy means that the frequency you set the generator dial to is also the exact frequency the generator is generating!

When Do You Need A Lab-Quality Generator?

Ready access to a good, professional lab-grade signal generator is a must for the serious radio aficionado—the type of experimenter who actively builds, modifies, and designs his own receivers, or who’s intent on getting the most performance from his equipment.

How often have you wondered if a recent alignment or the replacing of weak tubes measurably improved a receiver’s sensitivity? Or whether an attempt to “soup up” a vintage communications receiver by replacing the 6SK7 RF stage with a hotter 6SG7 really did any good? In theory a 6SG7 tube has a better noise figure and more to gain to overcome the noisy mixer stage. Is the sensitivity improved, or did the changes make the radio worse! And what did you give up in exchange? Is the dynamic range compromised, meaning the radio is now more prone to overload? These questions can be answered if you have the proper test equipment, and if you know how to use it!
 

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UTILITY COMMUNICATIONS DIGEST

U.S. Coast Guard To Continue HF Weather Broadcasts

by John Kasupski, KC2HMZ

 

As dutifully reported in this column some time ago, back in April 2007, the U.S. Coast Guard asked for public comment on the need for its HF high-seas weather voice, fax, and NAVTEX broadcasting services. The idea of seeing these services discontinued had originally struck me as potentially dangerous, especially for those smaller commercial operators who aren’t in a financial position to equip their vessels with expensive satellite equipment. Nevertheless, I offered no opinion in this space other than to encourage persons concerned to submit comments, so that the Coast Guard could weigh the need for its services against the cost of maintaining or replacing the infrastructure necessary to provide those services, much of which, according to the Coast Guard, has exceeded its reasonable life expectancy.

It occurred to me this month that since the official public comment period had long since ended (the comment period officially closed in August 2007), that it was time to revisit this subject and see what the public’s comments were. I did, in fact, do this, locating the actual text of the public comments on the Internet and reading through dozens submitted by people ranging from operators of small pleasure craft to captains and executives of large commercial operations. I wasn’t surprised when it turned out that the vast majority of comments were in favor of the USCG retaining its HF weather information services.

Armed with that, I was all set to write a column this month presenting these facts and urging the Coast Guard to continue to do its duty in helping to protect the safety of vessels, not only on the high seas but on America’s territorial waterways as well.

Then, the strangest thing happened…an agency of the government decided on its own to do the right thing! After analyzing the public’s response, the Coast Guard concluded that it was necessary to continue to provide these services and issued a report on its study of the situation, which you can find on the Internet using the link on the page at the following URL:

http://www.navcen.uscg.gov/marcomms/high_frequency/HF-WX_notice.htm

This is a lengthy PDF document, but the report’s conclusion is what matters. Quoth the Coast Guard: “The responding public collectively believes that the USCG HF broadcasts are essential to their safety. There is no viable alternative to the USCG HF broadcasts because present alternatives are perceived by the public to be out of financial reach. Also, marine weather forecasts available through these alternative sources may not guarantee the same level of accuracy, timeliness, and/or sufficiency as provided by the USCG HF broadcasts.”

The infrastructure in question—that is, the Coast Guard’s total HF infrastructure, consisting of 123 Rockwell-Collins HF80 and Harris RF-755 10-kW transmitters—has reached the end of its useful life because repair parts are ever harder to find and ever more expensive to purchase as these transmitters get older. We will undoubtedly see all but the most critical of the Coast Guard’s HF services discontinued, since the USCG does not have funding to replace all these transmitters.

However, the transmitters used for the HF weather broadcasts—a total of 20 Coast Guard transmitters along with three Navy transmitters on Guam that are used to broadcast HF weather fax, voice, and text (SITOR) forecasts to mariners for the areas shown in the accompanying Figure—will be replaced so that these services can be continued. These transmitters cost about $200,000 a pop with installation, according to the Coast Guard, bringing the bill for replacing the transmitters used in providing these services to a total of around $4 million.

 

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LOOSE CONNECTION

Friends Don’t Let Friends Have Split Ends…

by Bill Price, N3AVY (and Son)

 

It’s coming up on two years since I last saw Norm. Back when we worked together, we saw each other five days a week and at least one day on the weekend. I can’t say that I miss working on “the bus,”* with him, but I do miss having Norm near enough for those casual visits. For the last 14 years or so, we’re lucky to see each other once a year, and then it’s always been for too short a time.

I do get to daydreaming about some of our escapades. I know I’ve written about most of them here. Not all of them, though. Discretion being the better part of avoiding lawsuits, staying out of jail and all that.

I don’t believe that Norm and I ever spent a day of relaxation—something that good friends usually do together. Every time we went to a hamfest we were working, and were lucky to get a few minutes on our own to run through the flea markets to look for treasures. Even the great Dayton Hamvention found us scrambling to squeeze just a half hour roaming through the flea market during all those days spent there. We did have the advantage of being able to ship our treasures home in the “company truck”—something the folks who flew in and out couldn’t do (imagine dragging a seven-hundred pound transmitter to the baggage check-in at Dayton).

I remember using Norm’s chainsaw to clear away what seemed like an acre of undergrowth to make way for his guy wires at a tower-raising one cold Saturday morning. His saw was the only one I’ve ever handled which squirted gasoline onto the user at a faster rate than it used it to cut wood. I’m so thankful that no one in that crowd smoked. Moving his “Eisenhower” transmitter into his apartment probably caused me to have my hernia repaired a year or so earlier than I otherwise would have—and a word to the wise: A kW AM transmitter does not make for good neighbors in an apartment building. Of course, a concealed antenna in the attic of an apartment building is not recommended, either.

Installing that antenna during several lunch hours had us crawling through a trapdoor in a common hallway (while wearing jackets and ties, because we had come from work), and when a neighboring tenant wondered what kind of communication gear we were installing in the ceiling of the complex, I still wish Norm hadn’t said, “FBI, ma’am—nothing to worry about.”

And speaking of the FBI—something I’d like to forget—there was the night that Norm called me and told me he had some horrible guilt about something he’d done and asked me to come over right away, which I did.

When I got there, he looked as if he’d just come from the shower. He showed me the label on the back of a bottle of flea shampoo for dogs. I read it and said, “Yeah?”
“The bottom, old man. Read the bottom.”

I read: “Warning. Use of this product in a manner inconsistent with its labeling is a violation of federal law. Yeah?”

“I’m gonna call the FBI,” he said.

“For what?

“I got fleas from the dog and I used it on my hair. Then I read the label. I’m just sick about this,” he said.

“Norm,” I said. “You’re gonna call the duty desk at a district FBI office and tell them you want to confess and they’re gonna trace your call and send the local police here to surround the place before you can tell them you’re an illegal shampooer! We could be killed! If you don’t remember the last two times you’ve been in trouble with the law, and the difficulty you had explaining your way out of a perfectly honest situation, imagine how it’s gonna go when they get you for some charge of wasting their time with a phony confession about dog shampoo!”
 

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