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SCANTECH Tones—Who Needs Them?
Mention the word tone to many scanner
enthusiasts and you’ll get the same raised eyebrows or moan from most of
them. Tones are generally a source of aggravation for the scanner listener
as they have a habit of getting into the receiver in places where we don’t
want them. But there is an up side to all this noise.
In their simplest form, a audible tone can
simply be used to let those listening know that there’s something
important coming, or that an important situation is underway. The beep
that many police departments put out just before an all points bulletin
serves just this purpose. If you weren’t paying attention to the radio
before, you should now because there’s something important about to be
said. Our local police also use a “situation” tone that beeps every 30
seconds or so to let everyone know that there’s an emergency underway and
any non-essential traffic (like license plate checks) should be held or
taken elsewhere.
To read the entire article, subscribe to BROADCAST TECHNOLOGY
Go On
A DXpedition These days any seasoned broadcast DXer may wonder how one ever survived in this hobby without the Internet. Obviously the ability to communicate with large groups of DXers through bulletin boards, e-mail lists, and instant messaging has been a major asset to the hobby. On the other hand, trying to find valuable Internet resources can be frustratingly time consuming. An Internet search for any DX-related topic may return hundreds, if not thousands, of sites, some useful, many not so useful. To help you get through the noise, occasionally “Broadcast Technology” will feature websites found to significantly enhance the broadcast DX experience. Here are three recommended websites. You can go on a DXpedition without leaving home via DXTuners.com and V-Soft.com, and then check out the latest podcasts or create your own on Odeo.com.
That’s right, you can do it. And when you’re
not DXing, check out the latest podcasts or create your own. Here are some
outstanding websites and exceptional DX logs guaranteed to keep your radio
dial spinning all winter.
DX Tuners provides access to remote-controlled
receivers located in Australia, Canada, Germany, Ireland, Sweden, the
United Kingdom, the United States, and Venezuela. Here are some of the
special receivers as described by DX Tuners:
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Radio Broadcasting There’s No Shortwave, But You Can Still Try For Tonga’s Mediumwave Station! By Bob Padula The Kingdom of Tonga occupies some 700,000 square kilometers of ocean, but consists of only about 799 square kilometers of land area, comprising 171 small islands, fewer than 40 of which are inhabited. It lies in a time zone of UTC +13 hours, and the capital is Nuku’alofa, located on the main island of Tongatapu. The island is about 30 kilometers by 20 kilometers and is predominantly flat, with extensive cultivation of many varieties of crops and vegetables year-round.
The colonization of the Tonga Islands can be
traced back about 3,500 years. The origin of the first settlers is
unknown, but it is thought that there was immigration from the west, such
as the Philippines or the East Indies. It’s also believed that
pre-European colonizers of the island region of Samoa and Fiji were from
the same seafaring people. Over time, however, Tonga’s settlers lost
contact with their origins and the early people in Samoa and Fiji. The first fishermen built their homes around the coast and the farmers moved further inland where the soil was fertile. Villages and townships did not exist, nor was there any form of centralized government or currency. Instead, an elite class ruled over districts, which were subdivided to a middle management group who sublet these land holdings to the common folk/slaves. It’s not certain that all Tongans accepted this regulated form of culture. Tongans developed a complex family ranking system whereby the eldest female (and her descendants) held higher rank within the family than did the brothers.
Religion in the pre-European culture was
associated with violence and unrest. Great emphasis was placed on the
local spirits and ghosts who had a direct effect on daily life.
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HOMELAND SECURITY This month’s “Homeland Security” column is a bit of a departure from the norm. Rather than focusing on all that is bad in the world, for a change I decided to showcase a couple of items that I personally have used and find extremely useful in the pursuit of our radio hobby. I am constantly on the lookout for accessories and gear that will make life on the bands a little more tolerable and provide increased enjoyment. Without a doubt, one of the more exciting—and helpful—aspects of the radio hobby in the last few years has been the advent of the multi-mode HF+ transceivers that have flooded the market. Starting with the Vertex Standard (Yaesu) FT-817 transceiver (HF + VHF/UHF, AM/CW, SSB, FM and DATA modes plus a general coverage receiver), we’ve been treated to a wonderful assortment of very small, highly portable, battery-powered radio gear. It’s designed for a variety of applications, including QRP (low-power) operation from the shack, car or trail, and emergency communications. The tiny FT-817 really sparked a revolution within the ham radio hobby that has had major repercussions throughout the world. The FT-817 was soon followed by the ICOM IC-703+ (HF plus 6 meters), the Elecraft KX-1 (four-band CW-only transceiver with internal auto antenna tuner and battery pack), along with higher powered radios like the FT-857, IC-706, TS-50S, and the FT-897. In short, there is a whole world of portable radio gear out there to fit anyone’s needs. All you gotta do is look!
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The Eyes And Ears In war, many acts of bravery are unsung or forgotten with the passage of time. But in his autobiography, Reminiscences, General Douglas MacArthur helped immortalize the heroism of some when he wrote: After the fall of Corregidor and the southern islands, organized resistance to the Japanese in the Philippines had supposedly come to an end. In reality, it had never ended…I was certain that a great number of those indomitable defenders of Bataan and Corregidor had escaped into the mountains and jungle that they were already at work against the enemy. Unfortunately, for some time I could learn nothing of these activities. A deep, black pall of silence settled over the whole archipelago.
Two months after the fall of the Manila Bay
defenses, a brief and pathetic message from a weak sending station on
Luzon was brought to me. Short as it was, it lifted the curtain of silence
and certainly disclosed the start of the human drama with few parallels in
military history. The fire and the spirit of this indomitable nation
burned as brightly as ever. I knew that the remnant of my soldiers was not
abandoning the fight while they lived and had the means. The words of that
message warmed my heart. “Your victorious return is the nightly subject of
prayer in every Filipino home.”
To read the entire article, subscribe to WASHINGTON BEAT Capitol Hill And FCC Actions Affecting Communications APCO Urges Congress To Address Communication Needs
In testimony before the U.S. Senate Committee
on Commerce, Science, and Transportation, an executive with the
Association of Public-Safety Communications Officials (APCO) has recently
offered recommendations to improve communications following the
devastation of Hurricane Katrina. “Lack of coordinated incident command
and control, lack of direct support for communications centers and their
personnel, and the inability to communicate were obvious problems in every
area I visited,” said Willis Carter, APCO International first vice
president. He offered 10 recommendations for Congressional action to the
committee: • Make significant improvements in local, regional, and national interoperability.
• Plan and train for disasters.
• Fund to ensure that public safety
communications networks are built and maintained to withstand worst-case
scenarios.
• Allocate additional 700-MHz band spectrum
for mobile broadband operations to provide high-speed video and data to
and among public safety personnel and agencies in the field. • Consider public safety answering points (PSAPs) and other emergency communications centers as core elements of the first response structure. • Mirror telephone central offices supporting 911 tandems in locations sufficiently remote to allow for quick restoration of 911 services.
• Provide funds to assist PSAPs in their
upgrades for wireless E911 and other technologies.
To read the entire article, subscribe to COMPUTER–ASSISTED RADIO MONITORING
You Can
Do It— As I have been outlining in this column for the past several months, radio receiving and transmitting technology has undergone a significant transformation since the beginning of this decade. That transformation has been the switch from the use of “real” electronic components to “virtual” components in a new type of radio design called Software-Defined Radio (or SDR). SDR works by sampling large bandwidths of radio signals directly off the antenna, turning that information into digital form and then processing that digital information through digital signal processing (or DSP) software in a computer. As in the case of any new technology, the first casualty is generally the dominant technology that is replaced. Currently the primary radio monitoring technology that will be the most directly affected will be those radios using super-heterodyne (or simply, superhet) circuitry, which have been mass produced since the 1920s.
The nice thing about the old superhet radios
was that they were simple to build, so
anyone with a good understanding of electronic circuits could put one
together. Even for those who found the superhet radio complicated, there
were even simpler designs available, such as crystal radios. Therefore,
the true foundation for today’s radio monitoring hobby is that just about
anyone can put together a working radio.
To read the entire article, subscribe to POWER UP: RADIOS & HIGH-TECH GEAR
New, Interesting, And Useful
Communications Products MFJ Enterprises has reached back in time to when radio was king and brought back to life some of the most popular, classic antennas that gave the most powerful signals. These classic high-performance antennas give you a powerful, booming signal and need just two trees or other points for support! According to MFJ, the antennas are made of stronger, more durable modern materials, with some adapted to simple, direct coax feed, and are “hang and play.” The MFJ-62XX single-band, two half-wave element collinear array provides nearly 2 dB gain and twice the receiving capture area of a half-wave dipole, with direct coax feed and low SWR across the entire band. The MFJ-64XX four half-wave element collinear array gives a 4.5-dB gain and four times the receiving capture area of a half-wave dipole. It requires a balanced line tuner or a tuner with a balun for balanced lines. There’s no cutting, soldering, or trimming required. The antennas come assembled and include custom fiberglass center insulators, glazed ceramic end insulators and heavy duty seven-strand, 14-gauge hard copper element wire and solderless, crimped construction. The antennas can be mounted a quarter-wavelength above the ground, but perform best at a half- to three-quarter wavelength above ground. Lengths are 55 to 136 feet horizontally. The feedline and stub simply hangs from the antenna and can be bent at the bottom or pulled away at an angle to make installation convenient.
For more information and complete pricing on
these antennas, which range in price from $39.95 to $109.95, contact MFJ
Enterprises at 800-647-1800 or write to them at 300 Industrial Park Road,
Starkville, MS 39759. Visit MFJ on the Web at
www.mfjenterprises.com. Please
tell them you read about their new antennas in Popular Communications.
To read the entire article, subscribe to THE PROPAGATION CORNER
A Look
At Mediumwave DXing— The mediumwave (MW) broadcast band, also known in the United States as the AM Broadcast Band (or simply AM band), currently extends from 525 to 1700 kHz. In the United States and Canada, channels are spaced in even 10-kHz increments starting at 530 kHz. Elsewhere, channels are spaced in 9-kHz increments, starting at 531 kHz. The hunt for signals from far away AM broadcasting stations is an exciting activity, especially during the late fall and winter seasons. The distant stations you’re able to hear depend largely upon signal propagation. Propagation at these frequencies is very different than it is for frequencies in the high-frequency range (3 MHz through 30 MHz), varying depending upon the time of day, the season, and other factors.
For mediumwave, the most obvious factor for
good DX is the time of day. The D layer of the ionosphere almost always
absorbs mediumwave radio signals during the daylight hours. As a result,
nearly all mediumwave signals received during midday hours will arrive by
groundwave propagation, rather than by skywaves refracted off the
ionosphere. Groundwave propagation makes reception of signals over a few
hundred miles away unusual in daylight. At night, however, the ionosphere
refracts these mediumwave signals, making it possible for radio station
To read the entire article, subscribe to
TECH SHOWCASE The J-Pole antenna is one of the best known amateur radio antennas. It’s simple to build, easy to put up, and withstands the elements like a champ. Plans for building a J-Pole in one of its many guises can be found all over the Internet and in the back issues of this magazine and others catering to radio enthusiasts. In fact, there are so many plans for this antenna that it’s tough to figure out which one to use. As a new ham, and one who wanted to get on the air sooner rather than later, I decided that buying a J-Pole was the best option for me. The antenna I eventually settled on was KB9VBR’s All-Copper J-Pole www.kb9vbr.com/jpole.htm. I originally found this antenna for sale by its builder, Michael Martens, on eBay. The price was right and, best of all, I wouldn’t have to worry about soldering or tuning—the antenna is shipped already assembled and ready to go. Michael responded to a pre-purchase e-mail question very quickly, so I knew technical support wouldn’t be a problem. He builds these antennas himself and has made hundreds of them. Each antenna is individually tested before shipment, and mine arrived via Priority Mail within two days, well packaged in cardboard.
The antenna stands 69 inches tall, with the
radiator measuring 58 inches and the stub 19 inches. An SO-239 connector
is soldered on at the point of lowest SWR, ready to accept a coax cable
with a PL-259 fitting. I ordered the 2-meter version of the antenna, which
is tuned for 146 MHz and sports an SWR of 1.2:1 at that frequency.
According to Michael, the SWR is 1.4:1 or less throughout the entire
2-meter band. This version of the antenna will also load up on 70
centimeters, where the SWR is reportedly 2:1 to 2.5:1 between 445 and 450
MHz. Gain is reportedly 3 dB over a quarter-wave groundplane.
To read the entire article, subscribe to RADIO RESOURCES Commercial SSB For The Line Islands! One thousand miles due south of Hawaii, nearly on the Equator, lies a line of islands so remote that high-frequency SSB is their only reliable link. I’m talking about Washington Island, Fanning Island, and Christmas Island of the Republic of Kiribati. “These islands are largely cut off from the world, except for an occasional supply ship and maybe a day stop by a cruise ship,” says Carlton Smith, KE5EUL, a ham radio operator with a communications plan to allow Christmas Island to maintain medical comms up and down the Line Islands, Republic of Kiribati. “We have received permission from the Republic of Kiribati Ministry of Health and the Telecommunications Authority to set the frequency of our medical communications to 7312 kHz, upper sideband,” reports Smith. “The SSB radio system is replacing an old one that never really got off the ground. Our new SSB system will, for the first time, permit nurses on Fanning Island to communicate reliably with doctors and nurses on their main island, Christmas Island, and will undoubtedly alleviate suffering and save lives,” adds Smith. He recently visited these remote islands and, as a ham operator, could easily envision how a 40-meter “hop” from the Line Islands could easily fill in rock-solid communications.
Coordination was conducted over 20 meters to
an active ham, “Tek” T32LN, on Christmas Island. Coordinating with Smith
as well as a powerful maritime mobile shore station on the West Coast,
Ken, KB6EVR, it was determined that the Christmas Island hospital station
could be put back on the air with some needed repairs, but the equipment
at the other islands was damaged beyond repair in recent bad weather.
To read the entire article, subscribe to REACT IN ACTION
After The
Storm And More Hurricanes Katrina and Rita, which devastated huge swaths of the Gulf coast last fall, did do at least one thing worthwhile. They prompted the Board of REACT International, Inc. to establish the REACT Disaster Fund. The fledgling REACT Disaster Fund will focus on relief to ease the devastation caused by these two natural disasters occurring in rapid succession. You read and saw horror stories about the nightmare that haunted the authorities and the general public alike after the hurricanes leveled their double whammy at the beleaguered coastal areas of at least four states. Now REACT hopes to make a dent in the terrible losses resulting from the twin disasters. Readers can help to build up the new REACT Disaster Fund. It is an opportunity to contribute to a relief effort through an organization directly related to your radio hobby interest. It’s easy to do. Just visit the REACT website at www.REACTintl.org and click on “Donations.” You can make a secure donation to the REACT Disaster Fund using your credit card. All donor information remains strictly confidential.
Do it now so planning can begin for a rapid
REACT response. Please help while the idea is fresh in your mind. Your
generosity will be much appreciated by REACT and by those disaster victims
who will benefit.
To read the entire article, subscribe to
GLOBAL INFORMATION
GUIDE Good news is word that Radio Afghanistan is coming back on shortwave, and in fact may have done so by the time you read this. The new effort will involve a 100-kW transmitter and several antennas, which will beam programming to Asia, Africa, and Europe. The station’s transmission facilities will be at Yakatoot, which apparently is in or near Kabul. The Indian government is funding the facility. At this point, we have no information as to times and frequencies.
Efforts are underway to reinstate the annual
test broadcasts from Radio St. Helena, which had to discontinue the highly
popular yearly transmissions a couple of years ago when the point-to-point
transmitter it had been using was retired from service. Station Manager
Ralph Peters would be happy to begin the broadcasts again, but the station
does not have a transmitter (other than for local services) and has also
had to deal with a budget cut. A decision was due back in September, but
even if it turned out to be a “no” there’s always “next year.” So, it
wouldn’t hurt to contact them and let them know you’d like to see the
annual broadcasts back again. The manager’s e-mail address is listed as
RalphPeters@helanta.sh, but
mail we’ve sent has bounced.
To read the entire article, subscribe to THE WIRELESS CONNECTION
Heathkit’s
T-4 Signal Tracer— After fixing up a few nice old radios, you’ve probably discovered that it’s also nice to have the right test equipment on the bench when the need arises. We’ve talked about basic test equipment in past columns, but this time around, for the first Pop’Comm of 2006, we’ll be discussing signal tracers and how to use them to isolate and find problems in radios.
There are two signal tracers being used on my
workbench, which are shown in Photo A. Both are Heathkits; one is a model
T-4, the other is a later version, the model IT-12. Despite the difference
in model numbers and age, both share very similar circuitry. Heath
regularly changed model numbers and cabinet styles (note the knobs) to
impart modern, updated looks to their test equipment lineup, while keeping
the same circuitry inside! I suspect a lot of folks bought into the
latest-is-greatest syndrome. From what I can see, both of these units use
the identical circuit and internal components. Nonetheless, they also
probably stayed with proven designs that worked as intended and were very
reliable. We’ll also cover the restoration steps needed to ensure these
instruments will continue to give years of trouble free service.
A signal tracer allows the tracing of a signal
from the antenna through the set’s mixers and IF amplifier stages,
detector, and audio amplifier stages. This lets the technician locate the
exact point in the radio where the signal is lost or becomes overly
attenuated or distorted. The signal tracer requires a signal source, which
can be either a convenient local strong radio station or, better yet, a
modulated signal from a good signal generator.
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HAM DISCOVERIES Although I’d love to play on the radio all day—pausing only once each month to write this column—I still have to bring home enough bacon to pay the rent and electricity bills. To that end, I recently accepted a contract job helping three small, rural towns set up a wireless Internet system. The town fathers call it “high-speed” wireless, but by my standards it’s not even close to high speed, but that’s another story. The really disturbing part came when I watched one of the technicians sent by the company that provides the bulk of the wireless bandwidth install a transmission hub atop a 30-foot Rohn 25 tower that was itself bolted to the top of a 90-foot tall grain silo. In farm country, big silos provide a handy and inexpensive way to zip signals back and forth, avoiding the much higher costs associated with commercial tower sites, etc. In a way, the rural wireless companies are a lot like hams—taking advantage of alternative, non-commercial solutions whenever possible. And the lucky silo-owning farmers get 256 kilobits of reliable wireless Internet for free while their phone-line-bound neighbors are lucky to maintain 33-kilobit dial-up connections that don’t disconnect every few minutes.
Anyway, back to the scary stuff. The wireless
tech was installing the hub, antenna and the tower all by himself, in a
back corner of the lot, with nobody even glancing in his direction every
now and then! He’d climb the silo’s access ladder, pull up a tower
section, bolt it onto the top of the silo, climb down, climb up to the top
of the recently installed tower section, pull up another tower section,
bolt it on, etc., etc.
To read the entire article, subscribe to THE POP’COMM TRIVIA CORNER Radio Fun And Going Back In Time Q. When was the car phone invented?
A. Around the turn of the 19th Century
driving an automobile was considered a rather daring sport. Driving out of
town was considered the height of recklessness because of bad road
conditions and the scarcity of repair facilities. In 1908, Valdemar
Poulsen developed a wireless telephone. An American, Arthur Collin also
developed one the same year. It was touted as the ultimate accessory for
anyone touring the country in a powerful car. Collin’s customers were
supposed to be drivers at garages who would rush out to service the
disabled automobiles. Collin was a little premature. He also ran into
legal problems and spent a year in prison for stock manipulation. Q. Hitler tried to keep Germany and occupied Europe from listening to “foreign” radio stations. How did he do that? A. Heavy fines and threats of prison were first used. Then he simply took everyone’s radios away from them. Over a million were confiscated in Holland alone. Some people were “trusted” enough to keep their own radio with medium and shortwave frequencies. Those who couldn’t be trusted were able to buy a “People’s Radio,” which only picked up three stations. Transmitters were in Munich, Hamburg, and Berlin, and were all Adolph all the time. There was a boom in homebrew crystal sets, which picked up the BBC in London and Radio Oranje from the Dutch Government in exile just fine.
To read the entire article, subscribe to UTILITY COMMUNICATIONS DIGEST
MILCOM Above
30 MHz: Last month we had a brief overview of basic MILCOM and MILAIR antenna systems. We even detailed the most popular off-the-shelf monitoring antennas available from today’s manufacturers. But half the fun of military monitoring is experimenting, tweaking, and fine-tuning your antenna array so that it becomes the ultimate military/utility communications signal-sucking system!
With that in mind, let’s look at some antenna
alternatives that might inspire you to get out the soldering iron, spools
of copper wire, coaxial cables and calculators and build your own (or
modify an existing) VHF/UHF antenna masterpiece!
Designing an antenna is much more than
whipping out the calculator and figuring the length of a half-wave dipole
cut to your favorite frequency. As any antenna designer will tell you, it
is as much an art form as it is a science, but if you are as
mathematically impaired as I am, antenna design specifications listed in
technical journals are almost as confusing to decipher as a hormone-driven
teenager’s emotions. A great place to find over 40 PC-based antenna (and other) design programs is at www.ac6v.com/antsoftware.htm. Although most of the designs are for amateur radio receive and transmit antennas, with a little re-figuring they can be adapted to serve your MICOM/MILAIR needs.
To read the entire article, subscribe to SHANNON’S BROADCAST CLASSICS
Broadcasting
At 40— One of my old college roommates is always noting that, except for age 20, women hate any birthday with a zero in it. Maybe this phobia is true for guys, too, but I meet a lot of folks who are happy to be aiming for another year—and take pleasure in reaching even-numbered milestones. One of broadcasting’s first big birthdays was its 40th, widely celebrated by electronic and print media alike in 1962. A decade earlier, when TV was quickly capturing consumer attention, radio’s future seemed comparatively dim, so not a whole lot was done to celebrate broadcasting’s birthday number 30. To be sure, there’d been a bit of a splash in ‘52 about broadcasting’s birth, but most of the focus was on video’s future rather than audio’s past. By the early 1960s, though, the undeniably robust television industry and decidedly revitalized (by music and news-weather) radio business had the time, resources, and resolve to reflect on its glories.
Here, courtesy of Pop’Comm reader Tony Gates
of Washington, D.C., we’ll open this month’s column with a look at some
40th anniversary hoopla, as presented in a special 1962 issue of Sponsor
magazine that Tony kindly sent my way.
Though a shameless promoter of himself and the
Radio Corporation of America he controlled, David Sarnoff can be credited
with having possessed the wisdom to concentrate on the future, rather than
rest on past or even present performance. That is to say, as soon as
Sarnoff got RCA radio receiver production on its feet in the mid-1920s, he
set about building the National Broadcasting Company’s radio empire.
To read the entire article, subscribe to LOOSE CONNECTION Communication Humor, Taken To Extremes Communication humor. Now there’s a topic. Couldn’t get my !@#$%! phone line connected properly to the modem. Loose Connection! That’s what it was. I should have taken that as an omen and written this in a fountain pen and sent it to New York via the Pony Express, except they’re all extinct now. So, last weekend I got to speaking with a new guy at church and the conversation gets to Pop’Comm instead of the golden rule, and it turns out that he’s been a loyal reader for quite some time now. I was beginning to feel as if we should save this conversation for the parking lot as I thought of the moneychangers and all that stuff, so we did indeed “save it for later.” What would you say the odds are that I would run into a person who has actually been behind the microphone at a numbers station? Well, of course he can’t give an interview, and not much more data than you already can surmise on your own, which is almost nothing, except that he does appear to work for the government (ours, I think), and after I arranged a clandestine meeting with none other than Alice Brannigan in exchange for what I hope to be an interview which will crack the lid off the whole question of “what the heck are numbers stations anyway?” I find out that he’ll have to kill me if we discuss it. Oh well.
So, onto another topic. Have you communicated
with any machines lately? Of course, there are the voices in your car, and
you can talk to your computer. I have often been heard talking to many
inanimate objects, often rather crudely, but today I created quite a stir
in a local building supply store that rhymes with Chrome Fleepo.
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