TUNING IN

Post Traumatic Legislation Syndrome

 by Harold Ort, N2RLL

It’s not often any government—federal, state, or local—changes a law for the better. As a matter of fact I can’t recall any recent “change” that would be considered in the public’s best interest, though on the other hand, it’s easy for our lawmakers to enact those laws to swing in the government’s favor. They’ll tell you most laws are there to protect you, preserve freedom, and keep the bad boys and girls in line, but there are many laws that, well, in a nutshell, are just plain ineffective and never should have seen the light of day.

The ECPA (Electronic Communications Privacy Act) is one of those. Some states’ legislation that make criminals of you and me for having a scanner in our possession while “mobile” or using a radar detector (nothing more than a radio receiver!) in your vehicle also come to mind.

Not to be outdone by other states and the Feds, the Michigan legislature, back in 1929—that’s correct, 1929—passed MCL750.508b, what has become known as The Michigan Scanner Law. Simply put, that law said that it was a crime to have in a vehicle a radio receiver that could intercept police frequencies (it didn’t specify Michigan’s frequencies or Montana’s or if that receiver was connected to power or could still be in the unopened box). It provided folks the option of getting a “Permit For Use Of Short Wave Receiver In Vehicle” from the Michigan State Police. (I got mine a few years ago. Pretty slick, except, of course, a scanner isn’t a shortwave receiver, but then again that’s only the tip of the lawmakers-not-being-very-bright iceberg).

The law also exempted amateur operators and law enforcement officials. Seems to me, though, that if you’re going to allow amateur radio operators or others to have a scanner in a vehicle or allow other folks to get a permit to use a scanner in a vehicle, at least call it a scanner permit, not shortwave receiver permit!

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INFOCENTRAL


News, Trends, And Short Takes
Gordon West, WB6NOA,
Amateur Of The Year

by Harold Ort, N2RLL, Editor, and D. Prabakaran

When Hamvention 2006 opens in Hara Arena on May 19, three amateur radio operators will be honored for their contributions to the Amateur Radio Service. Gordon West, WB6NOA, a man responsible for helping to recruit many new hams, Riley Hollingsworth, K4ZDH, who helped bring improved enforcement to the ham bands, and Richard Illman, AH6EZ/W9, whose efforts helped develop a solution to BPL interference, have been named as recipients of this year’s Hamvention awards.
Pat Johnson, KC8ZZO, Hamvention Awards Chairman said the committee had a tough task selecting the winners from among a number of worthy nominees. “We were impressed with the quality of the nominations. We believe the winners all represent excellence in service to the ham radio community.”

Hamvention Chairman Jim Nies, WX8F, praised the winners, saying, “On behalf of the Dayton Amateur Radio Association (DARA) and Hamvention 2006 it is my distinct pleasure to congratulate this year’s Award Winners. Please join me in recognizing each of these gentlemen for their outstanding contributions to Amateur Radio and their many years of devotion to the amateur radio service.”
Gordon West, WB6NOA, was named Amateur of the Year for his efforts in recruiting and training many new amateurs, in addition to his lifelong involvement in ham radio. Starting in the late 1950s “Gordo,” as he is known by many hams, began an active involvement with ham radio that included working for some of the big names in the field and helping to develop several innovative pieces of equipment. In the 1980s West and his wife Suzy, N6GLF, began teaching ham radio classes at college and marine venues and began writing the ham training books. He is, of course, also a columnist for Popular Communications.

West is a fellow with the Radio Club of America, recipient of the ARRL Instructor of the Year award, and active on ham bands from 75 meters through 10 GHz, spending at least a couple hours every day on the air helping new hams make friends on the many nets he runs.

 

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Special Project:
A Simple Yagi For The 300-MHz Band

It’s Easy And Fun To Homebrew This Great Performer

By Kent Britain, WA5VJB

The 300-MHz band has become one of the hotter areas for scanner enthusiasts, but proper antennas for the band are few and far between. It’s time to change all that, so with a few easy-to-obtain parts and some good coax, you’ll be tuning the mil-aviation band with a home-built antenna that’ll knock your socks off!

These 300-MHz Yagis are from a family of “impedance-controlled” Yagis I’ve been designing for some years. Using advanced antenna design programs, and a few hours on the antenna range, a series of antennas using the structure of the Yagi itself for impedance matching have been the result. They’re easy to build, inexpensive, and perform great!

We’ll use 72-ohm coax because the higher impedance helps give the antenna a wider bandwidth, plus 72-ohm TV coax is cheap, plentiful, and offers lower loss than 50-ohm coax of the same size.


Construction

Wood is the easiest boom material to use, but almost any non-metallic material can be used. If you need to mount your antenna outside, a coating of spar varnish, wood preservative, clear spray paint, or just plain old house paint will help it last for years. A 3/4-inch-square or 1/2 x 3/4-inch hardwood works best, but cheaper wood and even wood dowels have been used.
Fourteen years ago I mounted several similar antennas inside my attic, and they still work fine. Plastic water pipe can be used, but I’m not a fan of PVC antennas.

 

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MILITARY RADIO MONITORING
ON VHF, UHF, HF, AND SATELLITES

The Civil Air Patrol: History And Frequencies

by Tom Swisher, WA8PYR

 

The largest military auxiliary organization in the United States today, the Civil Air Patrol (CAP), has an interesting and varied history, with duties ranging from civil defense during World War II to drug interdiction and Homeland Security today.

CAP had its beginning just before World War II, when local groups in New York and New Jersey formed the organization for the purpose of patrolling from the air. Getting into high gear after the attack on Pearl Harbor, CAP’s initial purpose was patrolling our shores by air using civilian volunteers, with “sub-chasers” operating from bases along the U.S. East and Gulf coasts.

Formally organized as the Auxiliary of the Army Air Forces in 1943, CAP units continued to serve in the interest of civil defense, flying cover for airports, coasts, and borders in search of infiltrators, as well as patrolling power lines, forests, and other strategic assets. CAP planes also flew as targets for anti-aircraft gunner and searchlight trainees by towing target sleeves for gunners to shoot. They flew many courier missions and provided valuable search and rescue operations, looking for downed aircraft.

After the war, CAP became the Auxiliary of the U.S. Air Force when it was made a separate service in 1947. CAP continued its civil defense function during the Cold War, even serving as satellite tracking targets after the Soviet Union launched Sputnik in 1957. The search and rescue function begun during the war continued, and today it’s CAP’s most well-known service.

CAP Today

CAP today is a non-profit organization with over 58,000 members and 27,000 cadets. Divided into eight regions, CAP is headquartered at Maxwell Air Force Base, Alabama, as part of the U.S. Air Force Homeland Security Directorate. It regularly provides many of the same functions it has offered since World War II, with additional functions including aerial security for major events, drug interdiction, and transportation of time-sensitive medical supplies.

 

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RADIO RESOURCES

“New” MURS Frequencies: Quite A Hit!

by Gordon West, WB6NOA

 

When the FCC released its Report and Order for the creation of MURS, (Multi-Use Radio Service), a new unlicensed VHF “Citizens Band” service, emergency responders were quick to investigate where these five “new” VHF channels (see box) came from.

The FCC’s Report and Order reassigned these five low-power frequencies from the Land Mobile Part 90 service, and reassigned them to the Part 95 Citizen’s Band Radio Service. No license would be required, and some interesting loopholes were found that would intrigue these emergency communicators, drawing them onto these five VHF channels. The personal radio steering group (PRSG) has some of the best chronology of all that occurred when the new MURS frequencies hit town. It’s found at www.provide.net/~prsg/murshome.htm.

Some of the questions would-be users were asking included the following:
• Is interconnection to a phone patch okay?
• Is there unlimited antenna height?
• What is the effective radiated power?
• Are there continuous transmission capabilities?
• Are there 151/154-MHz repeater operations?

The FCC studied hundreds of such questions and comments regarding this new MURS service, and made some adjustments on what would be permitted and what would be disallowed.

The Real Story!
In answer to these and other concerns, here’s the scope:
• No phone connections are permitted in the MURS service.
• Antenna height limitations match 27-MHz CB radio; that is, 20 feet above a structure or 60 feet above ground as maximum.
• Maximum transmitter power (2 watts) measured at the antenna output.

 

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You Load 16 Tons And What Do You Get?

Not Quite The Same As Loading No. 9 Coal, But Still A Real Task…

By Murray Green, K3BEQ

 

Those are the opening words to a song made famous by Tennessee Ernie Ford. Although recorded a long time ago, it can be compared to a recent project accomplished through the combined efforts of members of Washington, D.C. and Maryland local area amateur radio clubs.

The Green Mountain Repeater Association, the District of Columbia Metropolitan Amateur Radio Club, the Laurel Amateur Radio Club, and the Prince George’s County (Maryland) ARES/RACES all pitched in when Keith Poptanich, KB3EGL, purchased a 700-pound crank-up tower from a local ham and the call went out for help. That call was answered by nine hams and one non-ham. The combined club member response, some planning, strong backs, and one heck of a driver got the job done.

The participants were Keith, KB3EGL; Jim, WI3N; HD, K3HDM; Ev, WA3DVO; Ken, KB3IIE; Cape, N3TTX; Jim, WA3NSI (being a sight-impaired ham did not deter Jim); Lee, KM3DR; Bob, KC3VO; Jim, KB3KHL, and non-ham Rick. These guys have a lot of talent in areas other than radio. It took some doing to plan, maneuver, carry, and drive those 700 pounds of steel across town, but as one of them said at the end of the job, “piece of cake.”
 

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HAM DISCOVERIES

Summer On Six: A Magical Place

by Kirk Kleinschmidt, NTØZ

 

Summer is sizzlin’, or at least it will be when you receive this month’s issue! And summer is the hot zone for 6-meter activity here in North America. Hot weather equals hot propagation at 50 MHz.

Not too many years ago, 6 meters was a lot less accessible than it is today, especially for beginners. With the advent of compact DC-to-daylight ham rigs, however, most new radios have 6 meters on the dial. If yours does, but you still haven’t sampled the magic of VHF operation, there’s no time like the present!

What’s so special about six? Well, for starters, 50 to 54 MHz is an interesting, sometimes strange, VHF band that has some HF quirks thrown in for good measure. Propagation can be sporadic (pun intended), with no openings for a week, followed by strong openings to just about everywhere. Six-meter ops are universally friendly, and the equipment and antennas are physically small and easy to manage, whether at home or in the field. Once informally known as the “forgotten band” or the “TVI band,” 6 meters is now lovingly known as “the Magic Band.”

After a brief renaissance in the 1960s, 6 meters slipped into relative obscurity until the early ’90s, when equipment for that band became plentiful and affordable. Because most new amateur radio transceivers (mobile rigs included) incorporate 6 meters, and because we know a lot more about how 6 meters works, now is the perfect time to get started there.
If you think 6 meters is good only for local communication, press your reset button now. Although 50 MHz supports reliable groundwave communications up to 100 miles with low-power, long-distance propagation on the Magic Band starts taking off in the spring and summer of just about every year.

It’s Not Exactly Like HF

On the HF bands, signals are typically propagated via groundwaves or skywaves. According to lore, groundwaves travel a short distance before fading away, and skywaves—if we’re lucky—reflect from the ionosphere to the ground, and back again, covering longer distances.
 

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Here Right Now: Free AM And FM Digital Radio

There’s No Subscription Fee, And It’s On Standard Analog Frequencies!

By Bruce A. Conti

 

AM and FM radio is available for free, with digital clarity and without a subscription. It’s called HD Radio, and that’s the message legacy AM/FM broadcasters are sending loud and clear through the advent of high-definition digital radio, coming soon to radio stations near you, if not already on the air. It’s all in response to the growing popularity of subscription satellite radio.

FM radio stations are now multicasting with separate “HD2” secondary digital channels featuring commercial-free and unique music formats, such as lost oldies, disco fever, avant-garde jazz, and hardcore hip-hop, while providing a primary digital simulcast of the programming carried on standard analog frequencies. Digital technology also brings near FM-quality audio to AM, and near CD-quality audio to FM. It’s HD Radio moniker is intended to piggyback on the public’s familiarity with HDTV, and it’s here now.

Brief History Of Digital Audio Broadcasting

Digital audio broadcasting (DAB) has been under development for well over a decade. At issue were a number of factors. What spectrum of radio frequencies was available for digital radio? What form would the digital signal take? What would happen to existing analog radio signals?

One ambitious model that surfaced early in the debate allowed for digital broadcasting within the AM and FM broadcast bands in coexistence with analog signals. The objective was to allow broadcasters to convert to digital in stages using their existing assigned frequencies without interruption of ongoing analog broadcasts. This would in effect bypass a lengthy application and reassignment process for digital frequencies in a new broadcast band, ultimately making the transition from analog to digital as smooth as possible for broadcasters and listeners alike.

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PLANE SENSE

Pirates Of The Air,
And Orlando International Airport

 by Bill Hoefer

 

Interference to radio and television has been a problem since the early days of wireless. We get it from storms, power lines, the aurora, automobile engines—and sometimes other radio operators. Here in St. Pete, I’ve heard malicious interference on both 2 meters and 20 meters.

Interference on aviation frequencies is there, too. It’s nothing new but, amazingly, reports abound of malicious interference to our aviation frequencies. However, for the first time I can recall, there’s now a case of interference to air traffic from, of all things, a pirate radio station in Miami.

The mainstream media has recently reported that a pirate radio station, calling itself “Da Streetz” (107.1), had been periodically interfering with planes departing Miami International Airport (MIA). Kathleen Bergen, a spokeswoman for the Federal Aviation Administration, stated it was “…intermittent. Not all day, everyday.” The signals were traced to a nearby warehouse. Radio equipment, three computers, and a compact disc player were confiscated from the warehouse, but no disc jockey was found. The broadcasts, however, have continued on the Miami ATC frequency. Fortunately, pilots change to alternate frequencies in order to speak with ATC.

Federal laws, of course, prohibit anyone from transmitting over the radiowaves without a license. Florida also put an anti-piracy law into effect in 2005 that forbids anyone from interfering with a public or commercial station. In July 2005, the state shut down a pirate station in Fort Lauderdale and arrested two men. Also in the same month, it shut down a second station in Jacksonville. In all, the Florida Department of Law Enforcement (FDLE) has investigated six cases of radio interference. Those caught violating the state law face third-degree felony charges, up to five years in jail, and a $5,000 fine. Federal law is much harsher.

Seven years ago the FCC reported, “The FAA requested assistance 75 times to address such matters as unknown sources of interference on air traffic control frequencies and locating and silencing unauthorized transmissions on frequencies used for aircraft radar identification systems. In a few cases, individuals were intentionally jamming communications between the tower and aircraft, thereby jeopardizing the safety of landing or departing aircraft.”

 

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THE POP’COMM TRIVIA CORNER

Radio Fun And Going Back In Time

by R.B. Sturtevant, KD7KTS

Q. Who was the first President of the United States to own a radio of his own?

A. Warren G. Harding, 29th President, got a radio of his own in September 1920 while he was running for the presidency. First for the primaries and again in November for the general election, he tuned in along with thousands of radio enthusiasts. They all, through their earphones, heard that Harding had rolled over Cox with a great majority. Harding’s radio was the first to carry the word of victory to a newly elected President.
 

Q. How does GPS interface with radio and whose idea was it?

A. The Schneider Trucking Company was the first to install GPS transponders in their 400,000 trucks. Each vehicle constantly broadcasts its location, serial number, and load information. The system and the coded software that goes with it allows the management to locate any vehicle, driver, or load using GPS gear on the truck at anytime, anywhere in the nation.
The military found out about this system and applied it to their needs. Now commanders in the field can locate and identify every combat vehicle on the battlefield, tell who it belongs to, and if it is friendly or not. This has reduced the number of friendly fire deaths in Afghanistan and Iraq tremendously.
 

Q. Who invented the rectifier tube and when?

A. Like a lot of things this was a joint venture that happened a great deal by accident. Thomas Edison was working on the electric light bulb in 1883. Without explaining what he was up to, he instructed the glass blower who made his light bulbs to put a piece of metal in the end opposite the filament. That piece of metal was to be connected to the outside of the bulb by a small wire.
When the battery was attached to the bulb it was found that current would flow if the extra wire was attached to the positive side of the battery. If attached to the negative side of the battery no current flowed. This convinced Edison that a cloud of electrons (negatively charged) would flow through the added wire to the positive side but not if attached to the negative side. This was known as the “Edison effect,” but it was promptly forgotten about because it did not have application in the project at hand. It was noted, however, that the tube would change AC to DC, or rectify the current.

 

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HOMELAND SECURITY

CB Radio: Good For Emergency Comms?

by Rich Arland, K7SZ

This month we’re going to explore Citizens Band (CB) radio. It can be a vital part of emergency communications (EmComms), and there’s quite a bit of ground to cover, so let’s dive right in.

Waaaaaay back in 1958, the FCC decided to “give away” the 11-meter portion of the amateur radio bands and form the Citizens Radio Service. Up until that time, if you were a private individual and wanted to engage in radio communications you had limited choices. You could obtain an amateur radio (ham) license, with which you could not discuss business or commercial interests under any circumstances, or you could apply for a business band license, which meant paying very high prices for relatively low-power VHF FM equipment and a hefty licensing fee. Until the FCC set up the Citizens Radio Service there was no middle ground.

Being the FCC, and firmly believing in the bureaucratic process, the Commission proceeded to establish an all-encompassing set of rules and regulations in the form of Part 95. Licenses were required, callsigns were assigned according to various districts around the United States, and power limitations and antenna height restrictions were set in place. Initially the RF output power could not exceed 5 watts input to the final amplifier of the radio, and antenna height was restricted to 20 feet above the tallest manmade object.

In all, Part 95 of the FCC Rules & Regs was very much in keeping with Part 97, which governs the Amateur Radio Service. Licenses were issued for a small fee (around $5, if I remember correctly) and callsigns were meted out. After about six to eight weeks of waiting, your shinny new callsign arrived in your mailbox. Then you were “street legal” and able to get on the air on 11 meters. Strict radio discipline was expected and woe unto the Cursed Infidel who dared not adhere to Part 95!

Back in the late 1950s through the mid 1970s the FCC was a very powerful, sometimes vengeful, organization that struck fear into the hearts of even the most calloused individuals. They were the Radio Gods and their word was Law! Period! Dare to defy them and you would suffer the consequences.

My, How Times Have Changed!

My first exposure to 11-meter CB was in 1963 in Potlatch, Idaho, where a local farmer, Dave Walker, needed a summer hand on his ranch. Mom and Dad gave me the okay, and I went to work for Dave hauling hay, driving a bulk truck, and whatever else he needed. One thing about Dave, he was a forward-thinking individual. He had jumped on the CB bandwagon early on and had a vacuum tube CB transceiver installed in every vehicle he owned, one at his home as a base station, and one on his tractor and another on his combine. In a word, Dave was “radioactive!”

Having been involved in shortwave listening for many years and being in the middle of studying for my Novice class ham license, pairing up with Dave Walker was for me akin to Robin meeting Batman! We had a ball with the trucks, combine, hay bailer, and the radios! Dave’s callsign was 14Q0387 and I quickly became 14Q0387 Unit 2.

After a few weeks of working on Dave’s ranch, I cautiously brought up the subject of CB radio to my Dad, who managed the Arland Motor Company. The company, started by my Grandfather, George Arland, in 1903, was the oldest International Harvester dealership west of the Mississippi River (it closed its doors only in 1976). Back in the early ’60s, International Harvester had gotten into bed with the Raytheon Company, which coincidentally, manufactured 11-meter CB sets! Talk about an opening.



 

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WASHINGTON BEAT

Capitol Hill And FCC Actions Affecting Communications
APCO International Disappointed
In FY 2007 Budget

by Richard Fisher, KI6SN

Noting a “lack of adequate funding for dedicated first responder interoperable communications grant programs,” the Association of Public Safety Communications Officials (APCO) expressed disappointment in the President’s fiscal year 2007 budget.

“APCO International is concerned that there is no ‘dedicated’ [Department of Homeland Security] grant program for improving first responder interoperable communications” in the fiscal plan, the organization said in a statement on its website in February.

Officials also noted their “disappointment in the Administration’s intent to eliminate the Community Oriented Policing Services (COPS) Interoperable Communications Grant program, despite the program’s success.”
APCO called on the Bush administration to:

• Provide $100 million for the COPS Interoperability Communications Grant program;
• Provide $1 billion “in dedicated funding for emergency communications grants from the [DHS] to local governments”;
• Increase direct funding for the SAFECOM program
 

SAFECOM is “a communications program within the Office for Interoperability and Compatibility (OIC) that provides research, development, testing and evaluation, guidance and assistance for local, tribal, state, and federal public safety agencies working to improve public safety response through more effective and efficient interoperable wireless communications,” according to testimony before Congress.

“There are solutions and remedies to improving emergency communications during natural and manmade disasters,” the APCO statement added. “It is clearly time to provide focused grant programs for emergency communication needs independent of any other funding efforts.”
 

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TECH SHOWCASE

Alinco’s DR-635T Mobile/Base VHF+UHF Transceiver
And Expanded Range Receiver

by Harold Ort, N2RLL, Editor

 

When I received Alinco’s DR-635T for review my first intention was to give it a comprehensive, in-depth look with an emphasis on the many excellent ham aspects of this compact transceiver. I wanted to examine its cross-band repeater function, typical simplex range, signal quality, and how it stacked up against other mobiles I’ve recently used. But then it occurred to me that while these are important, there are many other features and aspects of this outstanding transceiver that warrant coverage here. Specifically, I mean the actual mounting of the radio in a vehicle as well as its extended frequency coverage (108 to 173.995 MHz, 335 to 479.995 MHz, and 87.5 to 107.995 MHz), which includes a sizeable portion of the VHF public safety band and standard FM broadcast band, plus a large chunk of the military aviation band! Talk about a versatile little dualbander!

We’ll still look at some of its two-way ham aspects, but I believe there’s a lot more to this rig than just amateur operation. Let’s check it out!

What You Get

Out of the box you get the EMS-57 illuminated remote control handheld microphone, DC power cable, bracket and mounting hardware, ACC port cable, and instruction manual. Oh, yes, and the radio! It only takes a few minutes to familiarize yourself with the basic operation of the 635T, even though there are a lot of goodies in a small (1.6 x 5.5 x 7.3-inch HWD) package.

The manual is clear and concise. Unlike some radio manuals I’ve seen, it’s free of mumbo-jumbo and was obviously professionally proofread before it went to the printer! While it’s not perfect, especially in the area of cross-band repeater operation, the 635T isn’t the type of radio you need to spend an afternoon with in order to use!
 

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SCANTECH

On The Right Track: Scanning Trains Across The USA,
And Floating Frequencies!

by Ken Reiss

 

Many radio users have frequencies within the spectrum dedicated for their use. This is particularly apparent with the aviation band of 108 to 137 MHz, which is also in the AM mode, but there are some others. Over the past several years, many of the “hard-and-fast” frequency allocations have been blurred considerably in an effort to shift frequencies from services where they were not being well used to services that were overcrowded in a particular area. This reallocation has been highly geographical in nature and depends entirely on what services are in your area and what frequencies might be available.

With some careful searching and research, frequency coordinators have been able to license many frequencies that are outside their “service,” making it more difficult for those of us trying to find those new frequencies. No doubt the refarming efforts that we discussed a couple of months back will complicate this as well.

One place where this has not yet happened, at least to any great extent, is the railroad service. The railroads’ allocated VHF frequencies have been in use for many, many years. While there was a proposal to move the railroads to another band at one time, it was dropped because of strenuous objections from the railroad industry itself. The cost of new equipment for different bands on a nationwide basis would have been staggering.

Case in point: The aviation service is currently under siege as the entire air traffic control system is evaluated for upgrades. I would expect, however, that it will be many years—if ever—before any changes actually occur for either aviation or the railroad service.

I have read in several places that there is another push to move the railroads to trunked radio. The problem is that the railroads have a lot of territory to cover. Putting up repeaters and trunking controllers along the thousands of miles of railroad track would be a tremendous undertaking.
 

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THE PROPAGATION CORNER

It’s All About The Noise—Part II

by Tomas Hood, NW7US

 

Last month, we took a closer look at atmospheric radio noise and its affect on radio signal reception. The original question asked was, “When will good propagation occur?” In the last two months, we considered the impact of noise, local and man-made, as well as atmospheric, such as lightning. At other times, this column has touched on some of the other factors that affect propagation, like radio circuit path length and orientation, frequency, diurnal effects, as well as the transmitter power and antenna gain and the parameters of the receiving station.

In our discussion last month, I mentioned radio propagation analysis and forecasting tools like WinCAP Wizard and ACE-HF. These can help you unlock the science of radio propagation at the high frequencies. More than ever before, with powerful computers available for reasonable prices, and with affordable tools like WinCAP Wizard and ACE-HF, any radio hobbyist can begin to make sense of all these factors that play a role in radio communications on HF.

A New Version Of ACE-HF—
Designed For Shortwave Listeners!

Back to our lingering question, “When will good propagation occur?” Whether you’re an amateur radio operator or a shortwave listener, noise is always a factor limiting what you can hear. But noise is only one aspect of HF reception. The varying ionosphere makes even powerful broadcast signals come and go, and it’s hard to know what to expect when you settle down for an evening of shortwave listening. Of course, you can always tune to the frequency where you last heard a favorite station, but if there is noise yet no radio signal, what then? It’s frustrating to just “listen in the blind.”

ACE-HF to the rescue! If you’re an amateur radio operator you’ve probably heard of the ACE-HF System Simulation and Visualization Software that was first released several years ago. This year, a much more powerful version, specifically designed for shortwave listeners as well as hams, is available. In this column I’ll describe the general features of ACE-HF and discuss how it can be used to predict shortwave reception.

 

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COMPUTER–ASSISTED RADIO MONITORING

Digital Signal Processing, Part II—
Learning The Theory Behind Today’s Digital Communications Technology

by Joe Cooper

 

No matter what type of modern communication technology you use today, whether cell phones, television, radio, PCs or CD players, all are becoming increasingly dependent upon digital signal processing (DSP). The same goes for software-defined radios (SDRs). All SDRs use DSP to produce the phased (I/Q) digital information characteristic of that technology. That phased signal is used to demodulate the intelligence contained in a digitized radio signal to turn it into usable information, such as voice or music.

I’ve touched on this topic before, for instance in the column on the set-up and operation of PC sound cards back 2002, as well as in 2003 when I outlined how to use those PC sound cards to digitally record audio signals. Even in the short time since I wrote those columns, there have been many improvements and refinements in the application of DSP, particularly in regard to radio-frequency applications.

DSP technology is itself not new at all. You can argue that it had its origins in the earliest forms of “the original digital”: telegraphy. Right from introduction of telegraphy in the late 1700s, there were many attempts to improve the quality of the signal by processing it in different ways. The placement of telegraph signals on wires via electricity was the starting point of our current electronic-based DSP technology.

The Modern Era

Modern digital recording techniques had their origins in theoretical work undertaken in the 1920s to improve the reception of telegraph signals at distant locations. The most famous early contribution was that of AT&T scientist Harry Nyquist. His research into improvements in telegraphy led to a very important discovery in digital recording: an analog signal should be sampled at regular intervals over time and at twice the frequency of the signal’s bandwidth in order to be converted into an adequate representation of that analog signal in digital form. That discovery was then used by Claude Shannon in the 1940s to develop the basic concepts that have led to today’s digital computers, CD recordings, and data compression.

 

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GLOBAL INFORMATION GUIDE

The International Broadcasting Bureau
Monster Strikes Again!

by Gerry L. Dexter

 

The U.S. government’s International Broadcast Bureau (IBB) calls the shots when it comes to things like language services, frequency choices, and transmitter operations for the Voice of America and other government-sponsored broadcast services. Lately the IBB has looked more like some terrifying creature out of a Stephen King novel, suddenly appearing through the fog of night to consume you while you’re still alive and able to scream.

Last month we told you about the huge cutback they’ve made in VOA broadcasts, resulting in a long list of abolished languages, times, and frequencies. Now the monster has risen out of the muck and mire to strike again. This time it’s the closing of the Rhodes and Kavala relay sites in Greece, effective with the B06 schedule in late October. Reason? Oh, it’s the usual. Too expensive to operate. And an audience that is moving to other means of access (Internet, FM, TV). At the rate things are going the VOA will end up ranking behind Swiss Radio!

Also, we wonder what effect, if any, this will have on the Voice of Greece relays via Delano/Greenville.

Radio Slovakia International—A Future?

Yes, no. Yes, no. Yes, no. Back and forth they go on the future of Radio Slovakia International. The latest word says the service is doomed and might even be gone by now. Such events are much regretted, not only for the loss but also for the shortsightedness of the governments responsible.

The Dominican Republic station which was active on variable 5010 three or four years ago is back in play, surrounded by the same past questions about its actual ID. Is it Radio Cristal? Or Radio Pueblo? Or maybe it uses both IDs? Radio Cristal IDs have been heard in the 5010 area off and on since the early 1960s
 

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THE WIRELESS CONNECTION

Our Majestic 90 Restoration—
Some Unexpected Problems!

by Peter J. Bertini

 

It’s been a long and challenging project, but the end is in sight! This month’s column will cover the final steps needed to bring the radio back to life. For our new readers, our subject is a large vintage 1929 Majestic model 92 lowboy console (Photo A). The set used a model 90 chassis (just to make things confusing) and was one of the earliest radios for battery-free AC line-powered operation when it was introduced in 1929.

So far we’ve covered the routine recapping and rewiring, the tedious expected tasks, now it’s time for a few unexpected challenges!

Pot Metal

Every new set brings new challenges and hopefully a learning process to make us better prepared for future projects. I had been forewarned to expect some “pot metal” problems in the Majestic before I started working on it. Boy, was that on the mark!

What the heck is pot metal? Well, pot metal means different things depending on what it was used for, and when. For example, pot metal used for cooking utensils used a much different formula (iron-based) from one used for automotive or radio parts (zinc-based.) For our purposes, pot metal is a castable zinc-based metal alloy with a low melting point. Differences in the alloy mixture gave the metal different properties, determined by the characteristics needed for the metal, such as machinability and durability.

Unfortunately, vintage parts cast from pot metal generally fare poorly over time. The metal distorts and, in the worst cases, it develops deep fissures and can completely crumble! The cause is corrosion at the grain boundaries in the metal. As the corrosion forms internally, forces are developed that cause the metal to expand and become misshapen. Acid (even brief exposure to tomato juice, for example) will greatly accelerate the problem. I suspect moisture and contaminates in the air work are major contributors to these problems as well.
 

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SHANNON’S BROADCAST CLASSICS

Radio Medford Via “Cheetah Bottom”

by Shannon Huniwell

 

To most people radio is little more than a light switch. They click it on when they want music, a bit of news or weather, but never consider how the broadcast comes their way. For this vast public, all radio and related radio terminology is alike. There are no nuances. A megahertz might as well be a kilowatt.

Maybe that’s why, despite my protests for more accuracy, I got tagged with the nickname “Short Wave.” Of course, the fact that I’ve never been much taller than five feet might have added to the appropriateness of the identifier. Even so, as I pointed out to the freshman classmate who christened me with the S-W nickname, it’s long been local AM and FM, not international transmission, that is my cup of tea.

She got her comeuppance, though, soon after branding me. A group of catty older girls in our Phys Ed class saw to that after their ringleader spotted her in some jungle print attire she’d inadvertently worn, not remembering it was a gym day. “Cheetah Bottom!” they bullied. That moniker stuck fast and unmercifully followed the poor kid all the way into those little captions under her senior yearbook picture. We’ve stayed in touch through the years, and it’s she who (though still happily professing to know nothing much about radio) often forwards me interesting tidbits suitable for turning into a Pop’Comm column.

“Found This For 50-cents At A Yard Sale—Your Friend, Cheetah Bottom”

So read a pink Post-It note adorning the colorful cover of a Winter ’61–’62 (No. 582) Radio-TV Experimenter edition, carefully padded in a fresh U.S. Postal Service envelope. A little arrow from my friend’s notation extended to the cover’s circular inset picture of a young woman with strawberry blonde hair. The model was shown seated in front of an all-band communications receiver, the cherry red nail polish on her fingers contrasting with some silver toggle switch the photographer undoubtedly instructed her to touch. “Hey Short Wave, looks kind of like you!” my old classmate had scribbled.

 

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LOOSE CONNECTION

Just What Norm Needs…

by Bill Price, N3AVY

 

I know that I will surely rot in heck for telling secrets about Norm, but Norm is, shall we say, frugal. No, on second thought, we shall not say frugal. Norm is so cheap that George Washington squints when Norm opens his wallet. Norm also loves surplus goodies, and I have found just the thing for him.

Now remember, this is the Norm who wants me to get on the air (which I have promised to do) so we can talk off line, even though the Internet gives us unlimited e-mail and, if we really wanted to, we could use Voice over Internet and talk. Actually, I hate telephones, cell phones, and microphones, even though Norm has given me a nice rig with a nice microphone, and in fact, he even gave me a huge tangled-up ball of wire that is to become my antenna once the weather becomes nicer.

Anyway, there I was in my favorite gun shop, which also sells some U.S. and foreign military surplus, and what to my wondering eyes should appear but a set (several sets, actually) of Scandinavian (Swedish, I think) field phones. I knew right away they were field phones because they had little cranks on one end. The interesting part, even though their Bakelite construction belied their age, is that they carried an Ericsson logo! I’m sure it’s the same company that made the successful jump to cell phones and similar electronics goodies.

So, while I was pondering getting a pair of these for old Norm (and knowing full well that he’d never actually connect them and use them), I noticed an unusual phonetic alphabet on a little brass plate atop one of the phones—and it didn’t begin with Abel, or Alfa, or even Aye (one of my favorite phonetic words for the letter A).

As I pondered this lovely pair of FEINDEN ESSNARS, I saw that there were 30 characters instead of the usual 26! This, I found out, is because there is an A with a little circle above it (that gets called “Ake” with the little circle above the A), then there’s another A with a straight line above it, sort of a long dash (that one is called “Arlig” with the dash above the A), then there’s an O with an umlaut (bet you didn’t know I knew what an umlaut was, did you?) over it (that’s two dots, for the umlaut-impaired), and for that you say “Osten” (and don’t forget the umlaut!). Finally, there is a U with an umlaut. To convey that to the person on the other end, you must say “Ubel.”
 

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