CB Radio Accessories:
Where To Buy Them
We All Need Accessories, But Few Retailers Are Willing—
by Alan Dixon, N3HOE/WPUC72Ø/KST8678
What a dichotomy we CB Radio Service operators are faced with when it comes to finding accessories for our CB stations. On the one hand, CB transceivers are available for purchase just about anywhere. They’re in “big-box” retail stores, such as Wal-Mart, in nearly every town, and of course you can find them in your local radio electronics chain stores everywhere, and sometimes even in auto supply stores.
On the other hand, finding
accessories in stores can be quite a challenge. Seems that everyone wants
to sell you a new CB radio, but other than the requisite antenna for
mobile operation, few outlets are interested in marketing accessories for
that new transceiver unit. Oh sure, we can find every conceivable radio
and accessory for sale on the Internet, but many of us would rather
experience the “look and feel” of in-person shopping. And this is no mere
sensory exercise. When we can personally examine merchandise before we buy
it, we feel confident that we know we’re getting what we’re paying for.
Well, retail floor space (and shelf space) is valuable and numerous products “compete” for available space by virtue of their potential— and actual—profitability. The real irony here, in my experience, is that vendors have the opportunity for a greater markup (translated as profit margin) on such accessories than on the radios themselves. Perhaps other products are, or simply seem to be, more profitable than CB radio accessories. Or perhaps so many retailers feel that CB operators’ personal discretionary budgets don’t provide for much in the way of accessory purchases.
But then again, perhaps so many retailers have never really given us hobbyists the opportunity to validate the profitability of accessories marketing. If they don’t dedicate the floor space to stock a full line of station accessories, then they will certainly never see how much money we really would be spending to build out our CB radio mobile and base stations!
For many years we all knew that we could find nearly every CB station accessory at our nearby radio electronics chain store. It appears, however, that many of these fine stores have in recent years substantially reduced their stock of CB radio-related accessories. It’s difficult to be specific without printed catalogs from which to search, but some things that were at one time readily available are now no longer obtainable, even by special order. Radio electronics chain stores are in many ways unlike other retail chains, so I won’t speculate on their reasons for moving in that direction. Suffice it to say I’m sure they have sound reasons for their business decisions. And one reality of business operations (here again, in my own experience) is that some business decisions are based more on the “bottom line” and less on customer convenience.
Interoperability: Problem Solved?
by Rich Arland, W3OSS
Ockham’s Razor: “When faced with a complex phenomenon, the simplest explanation is often the correct one.” Or, stated another way, the explanation of any complex problem or phenomenon should make as few assumptions as possible. Although often shunned by the die-hard scientific community as pseudo-scientific “mumbo-jumbo,” Ockham’s Razor finds its application in many areas other than theoretical science. Take for instance emergency communications and the multi-headed dragon of radio interoperability between responders and disaster mitigation professionals.
Without a doubt the largest single issue facing the disaster mitigation professional today is interoperability. Since September 11, 2001, very little, if anything, of great usefulness has been done to interface the multitude of dissimilar EmComm (emergency communications) radio systems to allow one service to trade information with another, despite the billions of taxpayer dollars thrown at the problem.
Why is this? If nothing else,
the events of that fateful day over five years ago showed us that we
lacked adequate communications between responding units, support units,
disaster command and control units, and served agencies. Add to this the
alleged interference caused to trunked emergency radio systems (FDNY,
NYPD, Port Authority Police, etc.) in New York City from a large cellular
provider and you have a basic picture of the chaos that followed the
suicide mission surrounding the World Trade Center. The problems were
witnessed again more recently during Hurricane Katrina. The only people
who didn’t have a communications problem were, of course, the amateur
radio emergency communications volunteers.
What is so darned hard about making several dissimilar radio systems talk to each other? Literally billions of dollars gone into this “interoperability problem” with little to show for the efforts. Making matters worse is the insistence of some political hacks who have a finger in the pie, so to speak, to buy non-APCO Plan 25 standardized protocol for digital radio systems (which has been around over 18 years). The picture is actually crystal clear: it’s MONEY! There’s a LOT of money out there to be spent by people hoping to hack the “interoperability problem.”
Interactive Ham “Hits” At Your Public Display
by Gordon West
Presenting the amateur radio
service to the public can be a rewarding experience with “live” equipment
demos at state and county fairs that include disaster preparedness
displays, simulated emergency test information stations, Field Day
information stations, and public display of ham radio.
Same thing with Morse code. As
you will see in this month’s photo column, straight keys and an oscillator
will develop a line of kids and adults eager to begin sending their names
in dots and dashes.
But there are some newer modes
that may be nearly a turn-off to the general public walking by your
display. The equipment may be modern, but the presentation a complete
bust! Say what?
The best presentation is one that is interactive.
You can have the best Field Day equipment and antennas in place, but if you don’t have the excitement and participation of the Filed Day players, here’s what you end up with—the public will not be impressed. (Photo A)
Digital modes operated with the
public looking over the ham’s shoulder are always a crowd pleaser. Don’t
forget to turn up the volume so the public can hear what PSK or packet
sounds like. (Photo B)
Tarheel Antennas’ “Little Tarheel II”
by Harold Ort, N2RLL, Editor
One of the most fascinating aspects of our multi-faceted radio hobby is antennas. You can have the best radio in the world with more bells and whistles than the Pentagon switchboard, but if your antenna is the pits, your signal will be the same. Thankfully there are folks like the ones at the Tarheel Antenna company who specialize in helping you get that signal—whether you’re a ham, CBer, or even mobile shortwave enthusiast—to and from the radio in good form.
I’ll get right to the main point: I’ve used the Little Tarheel II for several months and found it to be outstanding in every respect: construction, performance, and appearance. (Believe me, if you don’t think appearance is important, if you’re like many hams just try getting virtually any screwdriver antenna past your Better Half and you’ll see what I mean). Although my wife usually understands my radio cravings (that includes antennas, wires, switches, power supplies, scanners, etc.), she knows I understand that when it comes to mobile antennas, smaller is better, and the antenna shouldn’t be larger than the vehicle.
Having said that, an HF mobile
operator has a few choices, including single band whip antennas,
multi-band trap antennas, so-called “bug catchers,” and screwdriver
antennas. The choices are as varied as there are operators on the road,
but if you want a good all-around solid performer for HF operation
(including CB!) I heartily recommend the Little Tarheel II.
With the supplied 32-inch whip, the Little Tarheel II covers 3.5 to 54 MHz, but insert a 56-inch whip and you’re operating from 2.9 to 38 MHz! The antenna weighs about two pounds, and from base to mounting tip for the whip, it’s 16 inches tall. It comes with a 20-foot control cable and manual control box that you mount in your vehicle to change the “length” of the antenna, depending on where on HF you’re operating.
Think about it for a moment: If
you’re tired of stopping your vehicle to change bands at the antenna in
all kinds of weather and traffic conditions, or you just can’t mount an
outboard antenna tuner on your vehicle, the Little Tarheel II could be
just what you need. The antenna is small and great looking, too. You can
buy a beefier looking mobile antenna, but you’ll also need a beefier
mount, unless all your mobiling is done at the local park or in your
driveway. What fun is that? If you’re going mobile, go mobile!
A World Perspective—And Status In The USA
Digital Audio Broadcasting (DAB) has the potential to transform the traditional audio-based radio medium into a full fledged multimedia system, particularly suited to bringing digital information to the general public, anywhere and anytime. Digital radio has already become a reality in many European countries. It’s now possible to enjoy digital radio via various platforms, including DAB.
It’s vital for the success of DAB to work in harmony and synergy with some other systems, particularly those in the communication and Internet sectors. And it’s clear that DAB has to share the market and compete with other digital radio delivery systems like Wi-Fi, telematics devices, and the Internet.
DAB technology was developed by
the Eureka-147 DAB Project, which was set up in 1987. The Project ended in
1999 as a stand-alone organization and merged with the WorldDAB Forum.
Since 2000, the WorldDAB Forum has been responsible for the technical
maintenance of the EU-147 standard. The Forum, comprised of 90 countries
and several manufacturers, is now a central body for ensuring
international promotion and marketing of the DAB system worldwide as well
as lobbying international bodies such as the European Commission, European
Parliament, and the CEPT (Committee Europeene des Postes et
Telecommunications) for frequency spectrum management issues.
Whereas international cooperation is ensured by the WorldDAB Forum, the actual rollout of DAB services is in the hands of national broadcasters and national governments. Now that all major broadcasters and consumer electronics manufacturers have adopted it, DAB seems to have begun moving beyond the early stages. From the technology perspective, the value of DAB lies in better sound quality, more efficient use of the frequency spectrum, and the ability to carry additional data (non-audio) services, either associated with the main radio program, or not.
DXpedition Logs—Going The Distance To Capture Exotic Signals
by Bruce A. Conti
The DXpedition, an expedition
to a remote location for the purpose of receiving exotic broadcast signals
over long distances, is like radio listening on steroids. So you can take
part in the excitement, Pop’Comm presents the following partial accounts
of just a few of the premier mediumwave DXpeditions that take place around
the world, some on an annual basis. It’s extreme DXing at its best!
“Long Beach Island has been the site of one of the mid-Atlantic region’s larger mediumwave DXpeditions for the past several years,” writes Brett Saylor, a lead organizer of this annual event. Brett continues,
Each year’s results have been very different, depending on atmospheric conditions and antennas used. Long Beach Island, on the southern coast of New Jersey, has been the site of a weekend mediumwave oriented DXpedition held every autumn since 2002. Started by several East Coast DXers, it has attracted attendees from Connecticut, New Jersey, Pennsylvania, and Maryland. The DXpedition is held at a beachfront motel in the town of Ship Bottom, approximately 30 miles north of Atlantic City and 50 miles east of Philadelphia.
It seems that every DXpedition has its unexpected challenges, and Long Beach Island is no exception. In this day and age of heightened security, it’s easy for casual observers to be suspicious of unusual activities. That was the case for DXers Bob Galerstein and Dave Hochfelder in attempting to install an antenna on the beach. Bob relates,
While stringing the north Beverage antenna, our friendly local constable from the town of Ship Bottom pulled over in his SUV, got out, and questioned our intentions. While it was tempting to say we were spies (with thoughts of the Cappahayden locals’ feelings about the Newfoundland DXpeditions), we tried to explain the hobby. His response was to get permission from the town hall.
Antenna deployment was
temporarily suspended while Bob and Dave scurried off to obtain a proper
permit. It wasn’t easy, as Bob explains,
by Richard Fisher, KI6SN
An initiative adopted in part to promote interaction between U.S. radio amateurs and the Federal Bureau of Investigation “concerning critical infrastructure protection issues” brought a wide range of representatives together for a summit in July. Organized by New York Metro InfraGard, the one-day “Communications Interoperability and Ham Radios” session was held at Cisco Systems’ office in New York City. Keynote speaker for the session was Broadcasting & Cable Hall of Fame member and New York Public Television CEO William Baker, W1BKR.
“At its most basic level, InfraGard is a partnership between the FBI and the private sector,” the organization’s website explained. Described as an “association of businesses, academic institutions, state and local law enforcement agencies, and other participants” it is “dedicated to sharing information and intelligence to prevent hostile acts against the United States.”
“InfraGard chapters are geographically linked with FBI Field Office territories. Each InfraGard Chapter has an FBI Special Agent Coordinator assigned to it, and the FBI Coordinator works closely with Supervisory Special Agent Program Managers in the Cyber Division at FBI Headquarters in Washington, D.C.,” the site’s description continued.
After the July conference, Mary Hobart, K1MMH, chief development officer for the American Radio Relay League, which represents radio amateurs nationwide, said the session was “key to opening the door to a valuable model partnership. They were very receptive. I think it was a good beginning.” According to the League publication The ARRL Letter, Hobart said that amateur radio “came up on InfraGard’s radar earlier this year and got the nonprofit organization thinking of amateur radio as a possible partner, ally and service provider in emergencies.”
“They understand that ham radio
has ‘been there’ in terms of emergencies and disasters and is working to
improve its ability to respond,” she said, adding that New York Metro
InfraGard president Joe Concannon “expressed his deep interest in amateur
radio as a partner and a desire to learn more about our capabilities.”
Hobart also said, “Concannon envisions a model in New York City that other
InfraGard chapters across the country could emulate. I think it’s an
opportunity for amateur radio to align itself with a high-profile group
with key federal connections.”
THE PROPAGATION CORNER
Looking Forward With A Backward Sign
by Tomas Hood, NW7US
Since the start of 2006 we’ve been seeing a steady decline in the activity level of our solar system’s sun. Sunspots occur less frequently; there are periods now where we don’t see any sunspots for days. This signals the end of the Solar Cycle 23, but how will we know when Cycle 24 is starting up?
On July 31 the anticipated sign that Cycle 24 is beginning was observed. The sign? A short-lived tiny sunspot that formed up from the sun’s interior, floated around a bit, and vanished again in a few hours. This particular sunspot was special: it was backward.
“We’ve been waiting for this,” says David Hathaway, a solar physicist at the Marshall Space Flight in Huntsville, Alabama. “A backward sunspot is a sign that the next solar cycle is beginning.”
“Backward” means magnetically backward. Sunspots are magnetic regions on the sun with magnetic field strengths thousands of times stronger than the Earth’s magnetic field. Plasma flows in these magnetic field lines of the sun. Sunspots appear as dark spots on the surface of the sun. Temperatures in the dark centers of sunspots (the “umbra”) drop to about 3700 K, compared to 5700 K for the surrounding photosphere. This difference in temperatures makes the spots appear darker than the rest of the surface. They are seen to rotate around the sun, since they are on the surface (the sun rotates fully every 27.5 days).
Sunspots usually form in groups
containing two sets of spots. One set will have a positive or north
magnetic field while the other set will have a negative or south magnetic
field. The magnetic field is strongest in the darker parts of the sunspot.
The field is weaker and more horizontal in the lighter part (the
During the course of the average 11 years of a solar cycle, where solar activity rises and falls, swinging back and forth between times of quiet and storminess, the magnetic structure of the sun reverses itself. Right now the sun is quiet. During the peak of the solar cycle, the sun is very active and stormy. Right after the peak, the sun’s magnetic poles actually flip. At the end of a cycle, or at the start of a new cycle, sunspot magnetic poles flip.
So, when will Solar Cycle 24 actually begin? Since the first sunspot of a new solar cycle is always backwards, solar physicists look at July 31, 2006, as a very likely start of the new cycle. However, this does not mean that solar activity is going to immediately do an about-face. It can take up to five years for the next solar cycle peak to arrive.
Scanner Features—Part II
by Ken Reiss
This month, as promised, we’re
continuing our series on basic scanner features. And we’re going to tackle
a couple of tough ones this month, so let’s jump right in where we left
If you look at receiver specs, they’ll sometimes say something about conversion. Single conversion, double conversion, triple conversion, quadruple conversion. Why should you care? Well that’s probably worthy of an entire column by itself someday, but for now let’s look at the basics.
One thing is for certain: the more conversions a receiver has, the more likely manufacturers are to mention it. All receivers of modern design convert the received or desired frequency to something else before processing the audio. It can be done in one step, which would make it a single conversion receiver. Single conversion receivers are quite prone to interference for a variety of reasons. By adding a second stage (intermediate frequency stage, or IF for short), however, we can eliminate much of the interference. If you want to go further, you can add still another IF stage and have a triple conversion receiver. There is even one receiver that I’m aware of (although there are probably more at the high end of the government/industrial market) that is quadruple conversion—four IF stages.
So all of this conversion
business really comes down to interference rejection. You can have a
triple conversion receiver that gets interference, make no mistake about
that. But it’s much less likely to occur than with a double conversion
receiver if all other factors are equal. There are also some things that
double conversion receiver designers can do to their systems to make them
less interference prone, so don’t think that one is bad and the other is
not. Just different. You can expect to pay a bit more for a triple
conversion receiver, and you should be able to expect better performance
from it overall. Overall is the key word.
Continuous tone coded squelch system (CTCSS), also known by its Motorola trade name of PL for private line, has been the subject of our “ScanTech” columns before, and probably will be again as it’s a topic I get asked about on a regular basis. Here’s a condensed explanation for now.
THE ANTENNA ROOM
Scanner Antennas For VHF And UHF Monitoring
by Kent Britain, WA5VJB
Editor’s Note: Pop’Comm has asked antenna guru Kent Britain to do a regular bimonthly column on his topic of expertise. He starts with scanner antennas for the various VHF and UHF bands, and then goes over shortwave and CB antennas. Hey, certainly nothing wrong with covering several topics in a column! You can reach Kent with your antenna questions and topic suggestions at firstname.lastname@example.org. Welcome aboard, Kent!
We’ve got quite a lot of ground
in “The Antenna Room,” so let’s hit it running—there’s a lot to learn. I
also want to encourage readers to give their input for future columns, so
send in an e-mail and let me know what you’re interested in.
This month we’ll begin with a look at UHF antennas. These are part of a family of Yagi antennas designed to be simple and inexpensive to build. Officially they’re part of a family of over 80 “controlled impedance” Yagi antennas, but we affectionately call them “cheap Yagis.” (See Photo A.)
Don’t let their simplicity and
cost-effectiveness deceive you, you can really boost the range of 460-MHz
radios or the distance at which you can hear the 460-MHz business band and
public safety services on your scanner. They can also be used on the FRS
and GMRS frequencies!
The same driven element is used on all 460-MHz antenna versions covered in this month’s column. (See Figure 1.) The J element has about a 150-ohm impedance when mounted by itself. But as the other elements are added, the loading effects of these elements pull the impedance down.
So if I keep the elements a bit wide spaced, I can pull the driven element impedance down to 72 ohms. Now we have a direct
Mobile HF And The Modern Ham
by Kirk Kleinschmidt
Moving to another house can really be a pain. But the toil and trauma of moving furniture and toting boxes is nothing compared to the painful realization that—thanks to covenants and deed restrictions—you can’t even put up a decent antenna. Or even a crummy one!
Considering that I wrote a book about helping hams get on the air under these conditions—with hidden, disguised, or indoor antennas and a host of other sneaky techniques—you’d think that I could come up with an S-9 solution in a jiffy. I would, of course, if I could, put the neighbors (who live on the other side of the townhouse wall) to sleep for a few hours, find a supplier of finer-than-human-hair titanium wire that’s easy to solder, and develop the ability to see in the dark while remaining invisible, etc.
I haven’t checked the covenants and townhouse association bylaws for flagpole restrictions, and if there are none, I think a nice, patriotic 90-footer would look nice in the front yard—all 100 square feet of it!
As it stands, I plan to load the quadplex’s two-storey downspout with my trusty SGC autocoupler. I’m waiting for my hollow, fiberglass "garden rock" to arrive for camouflage purposes, and I have to wait until the neighbors are gone for the weekend so I can hook it up all sneaky-like. Running the counterpoise wire along the edge of the foundation will be trickier than connecting to the rain gutter.
If you think I’m whining, you’re absolutely right! My main alternatives are building a remotely operated station (I’d love to, but my wallet has flatly refused) or working mobile HF (a better idea!).
HF mobile operation keeps
getting easier, better and more affordable. Now that’s a real triple
whammy! What used to take a pile of massive gear and a rat’s nest of
unsightly cables can now be accomplished with a DC-to-daylight transceiver
the size of a Tom Clancy paperback thriller (and costs only a few bucks
more now that nobody reads anymore). Besides, if I can’t tarnish the
neighborhood with my demure skywire, they can’t stop me from mounting a
huge horizontal loop made from copper tubing on top of my van! And they
can’t stop me from parking it on the street in front of my house. Hey,
maybe the association will trade that eyesore for an invisible wire?
REACT IN ACTION
Where, Oh, Where Exactly Are You?
by Ron McCracken, KG4CVL / WPZX486
Fewer emergencies occur in winter than at other times of the year, but they can be deadlier. They are fewer because fewer travelers are on the highways, trails, etc. However, that also means fewer eyes to notice your tracks disappearing down an embankment or over a cliff. There are fewer ears passing by to hear your radio calls for help. A mishap that would be an inconvenience in summer can escalate quickly into a life-threatening incident in winter.
It’s always a good idea to
carry a GMRS, CB, ham, or FRS radio, but especially so in winter, at least
as a back-up to the cell phone. Cell phones are great, but in remote or
even rural areas they can be useless with no towers nearby to relay your
signals. Remember, cells are really two-way radios that require repeaters.
REACT volunteers can attest to that unfortunate fact. One California REACT Team reported that 94 percent of emergency calls its members monitored in a given period failed. Every one of those calls was heard. Each should have succeeded. Sadly, callers broadcast no key details monitors needed, and they could not hear REACT or police asking for the details.
REACTers were prevented from assisting by the very callers they were trying to help. But with good information, they could have had help quickly on the way. You wonder how many lives were lost needlessly. The radios worked perfectly; the operators failed badly.
From my base station in Ontario
I monitored a Kansas trucker who was snowbound in his big rig in a
blizzard. I listened for half an hour before I heard one useful detail. He
couldn’t hear my pleas for vital details. He spoke of fearing death and
being sleepy, but he said nothing of where he was. Not one word! Finally,
at 2:30 a.m. a lady switching
Somalia—Country In Crisis...
by Harold Ort, N2RLL, Editor
This month’s country of choice
has more fighting going on than the Hatfields and McCoy’s ever did—so much
so that you practically need a new board game to keep track of the
players. Last month, in his article, “DXing The Failed States,” Gerry
Dexter said that Somalia “has literally come apart at the seams.” Too bad
those in charge in this war-torn country don’t come to grips with that
reality. Somalia is always in the news, largely because of the constant
state of turmoil, which has gone from bad to worse over the past few
Famine and warlords grabbing pieces of Somalia are the hallmarks of this country that sits at the Horn Of Africa, with the Indian Ocean to the east and Ethiopia and Kenya to the west. Djibouti lies to the extreme northwest.
In this desert country that’s a little smaller than Texas but with a coastline more than 3,000 kilometers long, the latest “news”—which is really not much of a surprise—is that it has become a hotbed for terrorists, exporting those bent on doing the world harm to countries such as Iraq.
Somalia declared independence from an Italian-UK administered UN trusteeship on July 1, 1960, and has declared that date a national holiday: Foundation of the Somali Republic. The country is now run by a Transitional Federal Government with Transitional Federal President Abdullahi Yusuf Ahmed as chief of state, although the fractured government has yet to govern effectively. The actual head of the government is Prime Minister Ali Mohamed Ghedi.
The legal system, if you can
call it a system, is mostly non-existent, and largely means the many
regions of Somalia each work out their own conflicts based on customary
Somali law, Islamic law, or whatever passes for justice on any particular
day. There’s an estimated 8.8 million people living in the country (based
on a three-decades-old census), primarily between 15 and 64 years old and
nearly evenly divided between male and female. The next largest segment of
the population, also nearly evenly divided between males and females,
comprises those 14 years and younger; those 65 and older are under three
percent of the population. Life expectancy is about 49 years, with
food-borne diseases, significant use of contaminated water, hepatitis,
typhoid fever, malaria, and human conflict contributing to the figure.\
UTILITY COMMUNICATIONS DIGEST
Air: Breaking Down
by John Kasupski, KC2HMZ
Back in 2003, a well-known manufacturer of CPU (central processing unit) chips for computers conducted a survey which revealed that only a small percentage of people knew the meaning of 11 common terms of computer jargon. Over 1,500 people were surveyed, and only about three percent were able to understand terms such as megahertz, DPI, and MP3. Even among those people surveyed who actually used computers, only about two-thirds understood what the term "megahertz" meant. Never mind that some of us can toss around computer—and radio—jargon with the best of them.
The point is that, considering the fact that the survey was in multiple-choice format, insuring that some people were probably going to get it right simply by guessing, one can only conclude that there are an awful lot of people out there who find all that computer jargon bewildering.
It also occurs to me that some
computer terms (the aforementioned megahertz is one that comes immediately
to mind, along with "USB") are also a part of radio jargon. To make
matters worse, some of them, like USB, do not even have the same meaning
with respect to radio as they do with respect to computers! Therefore,
there are probably also an awful lot of people out there who find radio
jargon equally bewildering. This month we’re going to try to do something
about that, and right here in this column. After all, the “Utility” in
“Utility Communications Digest” is itself a bit of radio jargon; one
that—like megahertz and USB—needs explaining to those who haven’t long
dabbled in the shortwave listening arts like the rest of us have.
To begin with, let’s clear up
the jargon in the title of this column. To many people the term “utility”
conjures up images of last month’s utility bills from the electric or
telephone company. Moreover, although I’m aware of at least one such
utility that operates a network on the shortwave bands, that isn’t what we
mean when we talk about utility stations. The stations we utility
listeners like to listen to (which are called utility stations, of course)
are those stations on the shortwave bands that are not intended for the
entertainment of the general public, unlike shortwave broadcasters.
How To Eliminate Computer Noise
by Joe Cooper
During the past year, I’ve taken a detailed look at how digital sampling forms the foundation of modern radio communication. Radio engineers and scientists have always preferred digital modes of transmission to analog because digital modes add little or no noise to transmitted information, and today digital technology is superseding analog with breath-taking speed, making it the de facto standard of the 21st Century.
However, while we are rapidly moving toward a 100-percent digital world, there’s a significant amount of analog (or at least partially analog) equipment still in use. This is particularly true n the radio-monitoring hobby—and, unfortunately, many radios are experiencing a new type of noise as a result. I’m referring to what’s known as “computer hash,” which is the result of a computer’s CPU processing information at rates that correspond to monitoring frequencies. We’ve all heard this sound at one time or another, which can take the form of a loud and annoying buzz or pulse.
Interestingly, the first time this sound was ever heard over a radio was July 15, 1943, when the first secure digital voice communications took place over the SIGSALY system used by the United States and British military in World War II. The buzz of that digital transmission reminded people of angry hornets and it came to be called “the Green Hornet,” because it sounded like the theme song of the popular radio show of the same name. The buzzing confounded the Germans, as they were unable to decode the digitized information, thus helping to end the war.
Over the past few years,
however, as personal computers have become less expensive, making them
more numerous than ever, that buzzing noise is being heard on radios in
close proximity to the computers.
While they were never intended as radio transmitters, today’s digital devices are spewing out large amounts of digital hash on a wide range of radio frequencies. This is because when they process digital information, they do so at a frequency rate that spans the RF spectrum.
This phenomenon has been well known since the earliest days of digital devices and the FCC has been enforcing rules to keep such noise under control. Most of these regulations are found in FCC Part 15, which covers unintentional radiators of RF energy, such as computers and even TV receivers. These devices may generate the radio signals as part of their operation, but they aren’t supposed to transmit them. And while there are FCC standards intended to reduce interference to radios and TVs from digital devices, such rules cannot eliminate them.
GLOBAL INFORMATION GUIDE
Radio St. Helena Day!
by Gerry L. Dexter
Don’t forget that Radio St. Helena Day is coming up soon! Yes, we mentioned it last month, but in case you missed it, the return of these special test broadcasts from Radio St. Helena is scheduled for November 4 and 5 on 11092.5 USB and will run from 1800 to1930 for New Zealand, then 2000 to 2130 for Japan, 2200 to 2330 to Europe and 2330 to 0100 on the 5th for North America (UTC Sunday). There was initially some confusion over the broadcast times but the above is the latest as of press time.
This has been an exciting event in the past (the annual broadcasts ended in 1999) so, whatever you do, don’t forget to tune in and let them know they were heard and appreciated. And that second part holds even if you aren’t able to actually hear the broadcasts—it’s still very important to let them know their effort was appreciated.
A new Radio St. Helena QSL card
is being offered this time and there are some requirements to observe. For
instance, reports are being accepted by postal mail only (no e-mail
reports), and you must include at least three International Reply Coupons
(or a couple of dollar bills) to cover return postage. Letters should be
sent to Ms. Laura Lawrence, Manager, Radio St. Helena, Broadway House,
Main Street, Jamestown, St. Helena, South Atlantic Ocean. Please take the
trouble to write them, even if it’s just a thank you card!
The unusual Japanese broadcasts to North Korea (Shiokaze or “Sea Breeze” in English) are airing on a revised schedule. They’re currently heard from 1030 to 1100 and 1300 to 1330 on 9485 and also 2030 to 2100 on 9785, via Taiwan. The programs are produced by a group calling itself the Investigation Commission on Missing Japanese Probably Related to North Korea (COMJAN) and are broadcast in Korean, Japanese, and English, depending on the day of the week. Mostly they consist of a list of names of Japanese citizens who are thought to have been kidnapped by North Korea. Voice messages from relatives trying to provide some comfort and hope are also included.
SHANNON’S BROADCAST CLASSICS
“Percolator” Stations And Decaffeinated
by Shannon Huniwell
“I’d better warn you!” Broadcast Pro-File’s Jan Lowry advised, “That little Pennsylvania AM that you asked about is one of those “percolators” with almost no paper trail to research. It’s really not very exciting.” Jan was referring to WNAE of Warren. He’d assigned it to his so-called “percolator” section because, since 1946, the station has simply been percolating throughout a folksy portion of northwestern Keystone State airwaves without a whole lot of documented fanfare or change.
In fact, WNAE would never have been on my radar screen had not somebody in Montana come across a tiny WNAE promotional booklet and offered it on eBay. Apparently, WNAE wasn’t on too many eBay shoppers’ minds, either, as my initial—and admittedly rather measly—bid was the pamphlet’s sole suitor. After mailing the very modest check to the seller, I again contacted Jan (at 28243 Royal Road, Castaic, CA 91384-3028) to confirm an order for a WNAE Pro-File. He’d already spent several hours pouring through his broadcast history company’s voluminously overflowing file cabinets and bookshelves with the hope of culling at least a page of WNAE information.
“That old daytimer must have
truly been minding its own business!” Jan exclaimed. “Besides a power
increase, a short move to a new transmitter site, and a couple of
ownership changes, WNAE has been remarkably steady.” Though Jan should
have known I’d have been wonderfully pleased with whatever he could muster
up about WNAE, his mailing to me also included several other Pro-Files he
hoped “would prove more exciting.”
From my perspective, nothing at all. At last April’s National Association of Broadcasters convention I got to chatting with a gentleman and his wife who own three small market stations, each 1000 watts or less. The couple seemed quite surprised about my interest in their enterprises, and looked at each other incredulously when I took out my reporter’s notebook. “Tell me about your stations,” I invited, my pen poised to jot down every detail.
“Well,” they admitted with a
bit of a drawl, “There’s really not much of anything to tell. We’ve got a
nice audience, loyal employees, and enough advertisers to have paid the
bills and put our two kids through college—and one of them through medical
by Bill Price, N3AVY
It’s always a cause for celebration when Norm comes to visit, and this was no exception. Norm brought his new babe-magnet Jeep, towed behind “the bus.” Driving the bus meant he didn’t have to sleep on my new inflatable bed with the not-so-slow leak. Instead, he sawed wood in the bus, while parked by the woodpile, near the cows.
And where other RVs might have saunas or hot-tubs, this one has a comm center. Where most people install a generator on their RV for creature comforts, Norm’s generators’ first duty is to provide communication with the world. It powers a 100-watt HF station on what Norm calls “all the useful bands,” as well as two 2-meter rigs, a CB, and a scanner.
So we played with the radios and rode around town for a day or two, but on Saturday Norm had to take a day trip to visit a relative who lives a few hours from here. I would home. And that’s when the most devious idea hit me.
I actually know a person with a Class III federal firearms license, or whatever it’s called, that allows a person to own a full-automatic weapon, what you would commonly call a “machine gun.” I told Norm that if he’d spring for about 500 rounds of ammunition for this thing I’d see if I could talk this person into bringing it out to the farm for a little demonstration, since we have plenty of room to shoot. The truth is, I don’t know the person well enough to ask him to do that, but it did set the stage for the rest of my plan.
Norm gave me about $200 to pay for some ammunition for the thing, which I told him would be a classic “tommy gun.” I had not really expected Norm to part with that kind of money, but he let the moths out of his wallet because, like so many others, he wanted his one chance to play G.I. Joe, just like in the movies. I tucked the money in my wallet as he left to visit cousin whatzisname in Maryland, and told him we’d get to shoot the tommy gun the next afternoon.
Because I live on a farm, I
have access to a large, powerful air compressor, so I had no apprehension
about letting the air out of all five tires on the right side of Norm’s
bus. The bus listed beautifully to starboard, as I had hoped it would.