A Great Advance In DX—The Terminated Corner-Fed Super Loop
by Bruce A. Conti
The development of terminated broadband loop
antennas represents one of the most significant advancements for
long-distance (DX) mediumwave AM broadcast reception in recent years. Many
of these loop antenna designs were first developed by amateur radio
operators for applications in the 80- to 160-meter bands, later discovered
by mediumwave DXers to be useful in the AM broadcast band as well. The
following outlines the development of a variant antenna: the Terminated
Corner-Fed Super Loop.
Technically, the Ewe antenna is not a loop, but it does represent a starting point in the Super Loop development process. The Ewe was first introduced by Floyd Koontz, WA2WVK, for 80 and 160 meters (QST, February 1995). The Ewe is especially attractive to mediumwave DXers because of its relatively compact size and Beverage-like unidirectional performance, achieving a greater than 30 dB backside null.
The design is simple. It basically consists of two vertical wires connected at the top by a horizontal wire, thus forming the shape of an upside-down “U,” which supposedly gives this antenna its name. The bottom of one vertical is terminated to earth ground through a resistor, and the bottom of the other vertical is connected to the receiver via an RF matching transformer and coaxial lead-in. The separation of the verticals is typically 2.5 times their height. For example, if the verticals are 15 feet tall, then the horizontal length of the antenna should be approximately 38 feet, or 37.5 feet to be exact (15 x 2.5 = 37.5 feet).
These dimensions are generally considered the standard for the Ewe antenna, but as it migrated toward mediumwave DX applications, the dimensions were found to be very forgiving and adaptable to almost any situation. Patrick Martin, a prominent transpacific mediumwave DXer on the Oregon coast, has been using Ewe antennas of various sizes and vertical to horizontal ratios successfully over the years, in particular with a horizontal length of 100 feet, over six times the vertical height. I have used a “super-sized” Ewe in New Hampshire, measuring 50 feet tall and 75 feet long—a ratio of only 1.5—also with good results.
I soon became interested in the Ewe as a “stealth” antenna. I ran 50-foot verticals up the trunks of tall pine trees with the horizontal hidden in the canopy, using double-insulated 14-gauge stranded copper wire purchased at the local hardware store—perfect for a receive-only antenna. I tried the super-sized Ewe dimensions based upon the hypothesis that the tall verticals would improve reception of long-distance signals that typically arrive at low angles, and a larger antenna would provide plenty of gain, thus not requiring amplification.
The Ewe performance was outstanding, nulling
domestic signals to the west, while improving transatlantic reception over
previous random-length longwire antennas.
Here’s To The Control Operators
These Dedicated Volunteers
Are Always There When Needed—
by Murray Green, K3BEQ
Quietly, and from behind the scenes, control operators provide a necessary service for FM repeater users during day-to-day operations as well as during emergencies. But their efforts too often go unnoticed.
Most hams who use amateur radio repeaters typically operate while driving to and from work for short periods of time, and from home when not involved in raising kids, doing taxes, and performing household chores. Repeater licensees, trustees, and control operators, however, follow a different path. As volunteers, they monitor their respective repeaters most of the day and throughout the night. This is not as easy as you might think, because they’re placed in a unique position of having to hear everything that occurs on the repeater, including interference. What they do is often taken for granted, and many hams are simply not fully aware of what is involved in this daily volunteer service.
Some may think there’s a certain prestige in being a control operator for a repeater; it certainly requires a lot of patience, time, and discretion. Control operators, by virtue of their continuous monitoring, become very attuned to subtle changes in the repeater’s operation, a definite plus for those maintaining the equipment. They also listen to all types of exchanges and have to make decisions on illegal and poor operating practices. Sanctions, if required, must be diplomatically applied by control operators, who must make certain that they’re not censuring speech or causing ill feelings.
As a control operator, the last thing one
wants to do is create an atmosphere of self-importance or come down too
hard on a fellow ham. That’s the way to lose a current or potential club
member and create an atmosphere of unfriendliness that’s not in the best
interests of a repeater organization. Hams like to talk and word gets
around! Control operators must have that rare combination of being
assertive, straightforward, sensitive to the feelings of others, and
sincere in wanting to help. Not everyone is suited for that, so control
operators must be selected wisely.
During emergency situations our club repeaters (transmitting on 146.610 and 146.880 MHz near Washington, D.C., and maintained by the Green Mountain Repeater Association) are automatically turned over to the Amateur Radio Emergency Service (ARES) or the Radio Amateur Civil Emergency Service (RACES). Examples of when this has happened include 9/11, and numerous hurricanes, ice storms, and tornadoes. Also, many seriously ill persons are transported to hospitals for dialysis treatment, for instance, by ARES personnel during inclement weather when regular transportation vehicles are overloaded.
Although the repeaters are assigned Net
Control Stations (NCS) to help conduct an orderly flow of emergency
messages among participating stations, the control operators continue
their monitoring in the background. They stand ready to assist if
required, in addition to ensuring that the repeaters are properly used.
Hurricane Hunter Tour
Raising Awareness For What’s
Expected To Be A Very
by Bob Josuweit, WA3PZO
Don’t concentrate on a hurricane forecast’s black line. It could cost you your life. That was the message recently named National Hurricane Center (NHC) Director Bill Proenza, members of the NOAA hurricane hunter aircraft crew, and local meteorologists conveyed to hundreds of school children and visitors during the annual Hurricane Hunter tour, this year a five-day, five-city tour of the East Coast that began on April 30.
Proenza said the East and Gulf Coasts of the United States will continue to remain extremely vulnerable to tropical storms and hurricanes in the years and decades to come—especially since 53 percent of the U.S. population lives within 50 miles of the coast. The Atlantic hurricane season officially began June 1.
“Educating the public is our continuing mission,” said Proenza. “Even though last season had a below average number of tropical cyclones with no landfalling hurricanes, we remain in an active hurricane cycle likely to last another 10 to 20 years. Preparation through education is less costly than learning through tragedy.” The well-known Colorado State University forecasting team expects 17 named storms to form in the Atlantic, with nine of those storms becoming hurricanes. Five of the hurricanes are expected to develop into major storms (Categories 3, 4, and 5 on the Saffir-Simpson scale) with wind speeds of 111 mph or greater.
The NHC issues watches and warnings every time
a storm bears down on the Atlantic or Gulf Coast. Its mission is to save
lives, mitigate property loss, and improve economic efficiency by issuing
the best possible watches, warnings, forecasts, and analyses of hazardous
tropical weather, and by increasing understanding of these hazards.
Proenza explained that the NHC aims to be America’s calm, clear, and trusted voice in the eye of the storm, and, with its partners, enable communities to be safe from tropical weather threats.
“Although Bill [Proenza] has big shoes to fill as America’s calm and trusted voice in the eye of the storm, his experience and his ties to the emergency management community will be a national asset in preparing our coastlines for tropical weather threats,” said Department of Commerce Secretary Carlos Gutierrez.
“Bill directs warning and forecast services
for the most active severe weather region in the United States, the
Southern Region, where nearly 90 percent of our nation’s hurricanes make
landfall. He has made hurricane preparation and the local forecasting of
flooding, tornadoes, and high winds by our network of weather forecast
offices his top priority,” said retired Navy Vice Admiral Conrad C.
Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere
and NOAA administrator. “He is an effective and knowledgeable leader and
well respected by our partners in emergency management and the media.”
Listening To The Echoes Of Katrina
Nearly Two Years After
by Roberto Dabdoub, KB5AVY
Regardless of how much effort everyone is putting into the remaking of the New Orleans that once charmed the world with its food, music, and distinctive way of celebrating life, things are still looking gloomy in the Big Easy. Gloomy. And even still a bit frightening.
As a case in point, I’d recently just finished editing Rooftops Above the Water Line, a documentary about hurricane Katrina featuring the incredible rescue efforts of private citizens during the storm. I was exhausted and ready to turn in for the night when I heard on the radio that the National Weather Service (NWS) had issued a tornado warning for our area: “Expect sustained winds up to 40 mph and gusts up to 65 mph; a line of tornadoes was spotted and could be headed your way.”
The echo time web-driven program I installed in one of my ham repeaters was also going nuts. Earlier, Glen Boudreaux, N5RLT, our ham weather guru, had alerted us of this imminent threat. Fearing the worst again, with two FEMA trailers, a Ford Explorer, and two flooded sedans sitting in our driveway, there was little to do but find the safest place in the house.
My house is still leaning from the storm damage done by Katrina, so I wasn’t sure how sound it was structurally. But I sat and waited. (Trying to duck a storm with no place to hide is still a big problem in the Big Easy, and this year’s prediction of 17 storms forming in the Atlantic can really shake you up.)
One hour later, after the system moved away, we learned that the horrific storm destroyed 50 FEMA trailers, dozen of homes, and left 30-plus people injured and one dead.
Once again, poor communications delayed
Despite all the negative coverage the communications breakdown received during Katrina, a recent study showed that most public safety agencies still can’t effectively communicate with each other during “routine” emergencies.
In the wake of Katrina, most of the cellular and regular phone services were knocked out. Emergency workers inside the city were pretty much limited to a handful of Family Radio Service (FSR) handheld radios, and those frequencies were jam-packed and quickly overwhelmed. Plus, all those radios are line of sight and were also limited by their low transmitting power. First responders were unable to exchange essential information.
The federal government had previously expressed its commitment to improving interoperability among first responders. Prior to Katrina, the state of Louisiana had received $19 million in federal money to improve and upgrade its emergency radio communication system, funds that were used mainly to upgrade the state police radios. But what about the other services? They also needed to be upgraded at the same time.
What we now know is that this very upgrade created serious problems during Katrina, as the newer systems were incompatible with the older radio equipment still in operation. First responders simply couldn’t hear each other.
A friend told me something that he heard,
though; he heard a trumpet player on top of the Louisiana Superdome
playing S.O.S. with his horn (Dit Dit Dit...Dah Dah Dah...Dit Dit Dit).
Many people probably thought he was playing a jazz tune. My friend said,
“Then, I heard a gunshot followed by the crowd screaming.”
Lightning, The Deadliest Threat
Yes, It Can Be Fatal To Your
Equipment, But You’ve Got
by John Kasupski, KC2HMZ
When we think of summer, we tend to think of sunny days, backyard barbecues, baseball games, and beautiful rainbows. The old adage that there is no such thing as a free lunch applies: If you want to see a beautiful rainbow, you have to put up with the rain that comes with it, sometimes brought by thunderstorms, hurricanes, and tornadoes and sometimes marked by the high winds, hail, and downpours that can result in flooding. And that rain may be accompanied by the most serious threat of all: lightning.
Lightning kills more people every year than tornadoes and hurricanes. This is important to know since the primary consideration for anyone faced with a severe weather event is survival. According to the National Weather Service (NWS), lightning kills, on average more than 70 people, injures at least 300 others, and causes about $5 billion worth of property damage and other economic loss every year in the United States.
Lightning is very unpredictable. In fact, the only thing about it that is predictable is that it will be responsible for the thunder that you hear during a thunderstorm. When you hear thunder, there is lightning, and you are in danger from that lightning and need to take precautions.
Contrary to popular belief, lightning often strikes outside the area of heavy rain and may occur as far as 10 miles from any rainfall. The belief that there’s no danger from lightning if it isn’t raining is pure fallacy. This is especially true in the western United States where thunderstorms sometimes produce very little rain.
What we commonly call “heat lightning” is simply lightning from a thunderstorm that’s too far away for us to hear the accompanying thunder. That’s a good thing, because you’re in danger from lightning if you can hear thunder. However, if you’re curious about how close the lightning is when you hear the thunder, you can use the “flash to bang” method to estimate the distance from where you are to a thunderstorm by counting the number of seconds between a flash of lightning and the next clap of thunder. Divide that number by five, and that’s roughly how many miles away the thunderstorm is. If you see lightning and it takes 10 seconds before you hear the thunder, then the lightning is 2 miles away from you.
If that’s too much math for you, use what I
like to call the “30/30 Rule”: If the time between seeing the lightning
and hearing the thunder is less than 30 seconds, you probably should be
inside already. Where does the other “30” come in? More than half of all
lightning deaths occur after the thunderstorm has passed—you should stay
inside for 30 minutes after hearing the last clap of thunder.
However, don’t assume from the above that you’re necessarily safe as long as you’re indoors. That’s a nice, comforting thought, but it’s a myth. If a lightning bolt hits your house or a nearby power line, it can travel into your house through the plumbing or the electric wiring. If you’re using electrical appliances or plumbing fixtures, including telephones and computers, when a storm is overhead, you’re putting yourself at risk.
In fact, four to five percent of people
struck by lightning are struck while talking on a corded telephone, so,
here’s lesson number one: If you MUST talk on the telephone during a
thunderstorm, use a cordless phone or a cell phone. If it’s a cordless
phone, stay away from the base unit, and if it’s a cell phone, don’t leave
it connected to the charger that’s plugged into the wall.
GLOBAL INFORMATION GUIDE
Radiodifusion’s Blown Tube, CFRX’s Antenna Fried, And More
by Gerry L. Dexter
If you’ve recently noticed a particular absence on 6060, 9690, 11710, or 15345, the missing signal was probably that of Radiodifusion Argentina al Exterior. Late word had one of the RAE transmitters with a blown tube and the downtime for such an occurrence can run from an hour or two to a couple of months or more, depending on a variety of factors. We’re hoping this one will be on the short side and that, by the time you see these words, we’re talking history!
CFRX-Toronto continues in silent mode, leaving 6070 to whatever lies underneath these days, usually CVC’s La Voz, from Chile. Turns out that the CFRX antenna system took a lightening hit, which caused a nervous breakdown in the transmitter, so the problems are more serious than originally believed. According to Charles Maxant in West Virginia the station’s engineer-in-charge says the shortwave will return, though there’s nothing akin to a specific timeline.
That new station in the Central African Republic destined for 6030, which we mentioned last month, is using the name Radio ICDI (for Integrated Community Development International) and also Radio Tuma Yere, which is probably a localized version of the English name. Whatever. No one in North America has reported it yet and I’m not holding my breath.
Ditto for Dunamis Shortwave, also mentioned here a month or two ago, now said to be active from Uganda on 4750. But as things stand at the moment we can just forget about reaching for the tuning knob. This new religious broadcaster is operating in the middle of our daytime—1500 to 1900—so unless or until they significantly expand their schedule we can forget about this one as well.
The Zimbabwe opposition broadcaster, SW Radio Africa, may have a new fat-wallet benefactor, as it has recently added more outlets in an attempt to defeat the jamming harassment from Mugabe and his gang. 4880 remains in use from 1700 to 1900, but also being employed at those times are 11775 (via Moscow), 11810 (via Meyerton), 11975 (Kvitsoy, Norway), and 12035 (Rampisham). Some of the transmitter sites noted are based on educated guesses.
It may still be possible to catch Finland on shortwave, despite YLEs skeedaddle a few months ago. Polish Radio is supposed to be using the Pori site for one of its relays. It’s scheduled on 7170 from 2100 to 2200 (in Polish), which will make it a marginal possibility right around the time the A-07 season ends in late October.
Now they’re saying that, before long, we should get ready to kiss Radio Budapest goodbye! The only activity left will be a domestic relay on shortwave in the native language. Didn’t you think these East Europeans had more smarts?
Would you believe that the VOA’s Greenville, South Carolina, site is also in trouble? Actually there have been two sites there all along, ingeniously differentiated as “A” and “B.” Use of the “A” site was discontinued some time ago and its only purpose now is serving as a used parts supply house to keep the “B” site operating. What with the drastic downsizing of VOA languages and services you have to wonder what sort of lifespan the remaining installation has and what will happen when the “B” site is no longer operable. Maybe it will be time to hire some of the engineers from Radio Havana Cuba. They seem to have a special talent for keeping things going while working with the electronic equivalent of rubber bands and paper clips!
In contrast to VOA’s ill-considered pullback, Radio Ukraine International is increasing the amount of English on its schedule. English hours are now 0000 to 0100 and 0300 to 0400 on 7440, 0500 to 0600 and 0700 to 0800 on 9945, 1100 to 1200 on 15675, 1900 to 2000 on 7490, and 2100 to 2200 on 7510.
The wild world of relays is on a path to even
greater confusion. Deutsche Welle has discontinued use of its powerful
Wertachtal site and now transmits only from Nauen in the former East
Germany. The remaining DW transmissions come out of Ascension, Rwanda, Sri
Lanka, Russia, England, Portugal, and the UAE, and perhaps even others
beyond those. Don’t look to the DW website for any help figuring out
what’s where. A careful check offers nothing, even though it’s the one
thing you’d think it should certainly include!
Morse Code In The No-Code Era
by Kirk Kleinschmidt, NTØZ
Now that Morse code D-Day (February 23, 2007) has come and gone, U.S. hams aren’t required to know squat about Morse. Period. The U.S. Coast Guard stopped listening for Morse code calls, distress or otherwise, in the mid 1990s. Everything, or so it seems, has gone digital, high-tech, or satellite!
Isn’t it ironic that, in this era of “code demise,” that TV satellites, among other orbiters, still broadcast their transponder IDs in Morse code! Satellites are satellites by definition—and they’re certainly high tech. And Morse is digital. It’s a single-carrier, on/off digital code that’s processed in the time domain, unlike most “modern” digital modes.
Time-domain codes require lots of fuzzy logic and parallel processing to successfully decode. Computers aren’t too good at it, but the human brain is! And when you add signal fading, interference, and noise, the human brain, arguably the most advanced analog computer ever developed, leaves “digital” computers in the dust.
So, if it helps you to see Morse code in a new light, just remember that Morse code is digital, and that the best computer for demodulating its on/off, time-domain code is your brain!
That revelation aside, why should you bother
with an “abandoned digital mode” now that it’s no longer required for
Communicating via Morse—when you can speak it fluently, like any other foreign language—provides a hard-to-define intimacy that’s difficult, or impossible, to experience with SSB, RTTY, or whatever.
Maybe it’s because your brain is so involved with generating and decoding Morse. If you close your eyes when listening, an audio “landscape” opens up in your headphones (always the best way to copy Morse). Sounds take on a spatial quality. Noise might come from slightly to the left in your personal soundscape, while signals, desired and otherwise, seem to come from all over. Your brain, the fabulous fuzzy logic processor that it is, somehow sorts all this stuff and locks in on the desired signal. Communication results. It’s a lot more involved than trying to pick out a weak voice signal in the noise, or even from among multiple voices.
A Pair Of FRS/GMRS
Transceivers (With NOAA Receive!)
by Rich Arland, W3OSS
A dramatic question, yes, but an important one. Seriously, what price tag do you put on your life, the lives of your family? I sincerely hope it’s more than $69.95 (plus tax), because that’s what a set of Motorola Model T9500, FRS/GMRS transceivers will cost you at Home Depot. Are the lives of your family members worth a paltry $70 bucks? I’d say so.
Previously in this column we’ve discussed the
Family Radio System (FRS) and the General Mobile Radio System (GMRS)
series of handheld transceivers that seem to be flooding the consumer
electronics market these past few years. This month we’re going to cover
some of the same ground, but with the added twist of keeping you and your
family safe and sound during the severe weather season; as a matter of
fact, this system will be very helpful all year around.
Well, I’d like to say that they were on sale…but, I can’t. I was roaming around Wal-Mart about a week ago and ultimately gravitated to the sporting goods section (my wife, the beautiful and talented Patricia, KB3MCT) knows that’s where I will be should we be separated in the Wal-Mart super center for more than five minutes.
I was lusting after a very nice Leopold 3-9 variable rifle scope for my 30-06 when my eyes strayed over one case to glance at some GPS receivers that were on sale. Right next to them was a little yellow Midland radio that was an “All Hazards” NOAA weather receiver, built very much like an FRS/GMRS transceiver. That immediately got my attention and I asked to examine it. The price of the little NOAA All Hazards receiver was $39.95 (plus tax), which initially I thought wasn’t such a bad deal.
Flash forward a week and I found myself in Home Depot looking for a new lawn mower and weed-whacker (ah, the joys of home ownership!). Wandering around the huge home improvement store, I spied some blister packs of FRS/GMRS handheld transceivers. I absolutely love the advertisement on range: “10 Mile Range!” Yeah, right! If you believe that I have a bridge in New York that links two of New York City’s finest boroughs that I will sell you for a great price!!!
I looked over the various offerings and spied, on the Motorola T9500 set, a little statement that really got my attention. I looked over this set closely and decided to invest my $69.95 (plus tax) in short order. I had to try these two little gems out; they’d compliment the other three sets of FRS/GMRS handhelds strung through the house, two vehicles, and our Scamp camper. Redundancy that is the name of the game!
The Motorola Talkabout Model T9500s that I
bought at Home Depot are not just your garden variety play toys you find
in many stores. In addition to the normal FRS/GMRS channels, these units
also provide a NOAA All Hazards receiver! Now that is something unique and
well worth the $70 investment.
MILITARY RADIO MONITORING
Welcome To Fleet Week And
Willow Grove Base,
by Tom Swisher, WA8PYR
First held in San Diego (then-home to the U.S.
Pacific Fleet) in 1935, Fleet Week is a celebration of the Naval and Coast
Guard services of the United States. Various active-duty ships of the
fleet will visit the host city and tie up for a week, during which their
crews can visit and learn about the city, while the city’s residents can
visit the ships and various displays to learn about the Navy, Marine
Corps, and Coast Guard. Fleet Week often also features shows and
demonstration teams, such as the Blue Angels.
Fleet Week San Francisco includes vessels of the Canadian Navy and Coast Guard; participant vessels of Fleet Week San Francisco 2006 included the aircraft carrier USS Nimitz (CVN 68); the amphibious assault ship USS Bonhomme Richard (LHD 6); guided missile destroyers USS John Paul Jones (DDG-53), USS Higgins (DDG 76), and USS Chafee (DDG 90); guided missile cruiser USS Princeton (CG 59); Coast Guard cutter USCGC Steadfast (WMEC 623); and the Canadian Maritime Coastal Defence Vessels HMCS Edmonton (MCDV 703), HMCS Brandon (MCDV 710), and HMCS Saskatoon (MCDV 709). While the lineup for Fleet Week San Francisco 2007 is not finalized, it should certainly be an equally impressive display.
Participant vessels in Fleet Week New York 2007 include the amphibious assault ship USS Wasp (LHD 1); the guided missile frigate USS Stephen W. Groves (FFG 29); guided missile destroyers USS Winston S. Churchill (DDG 81) and USS Oscar Austin (DDG 79); guided missile cruisers USS San Jacinto (CG 56) and USS Hue City (CG 66); and Coast Guard cutter USCGC Katherine Walker.
If you visit any Fleet Week celebration (the
timing of the events vary according to city) and want to monitor the
action, start with the regular VHF maritime channels. These will be
hopping with a great deal of activity—as ships arrive and are docked as
well as during the shows and celebrations—with traffic from the various
vessels that one finds tooling about a major port. If the Blue Angels or
another demonstration team are scheduled to appear, be sure to monitor the
frequencies listed for them in various locations on the Web. And don’t
forget to use the search, Close Call or Signal Stalker function of your
scanner; these can offer invaluable ways to locate those interesting
With a varied history and critical strategic location, Naval Air Station/Joint Reserve Base Willow Grove is well situated for a variety of military functions.
Built in 1926 as a private airfield used for
research and development, the field was sold to the Navy in 1942. It
became an important facility for anti-submarine patrol aircraft due to its
strategic location near Philadelphia and other major East Coast ports.
THE PROPAGATION CORNER
Urgent! Only Two More Seasons Left! For TV DXing, That Is.
by Tomas Hood, NW7US
If you don’t start now, the opportunity to catch the somewhat rare NTSC (National Television Standards Committee) television signals from stations several (or more!) states distant may well pass you by. On February 17, 2009, the official switch in the United States from the NTSC standard of television broadcasting to the new digital standards will mark the end of your opportunity for DXing VHF NTSC signals.
These NTSC signals from stations hundreds of
miles away can reach your station by way of sporadic-E (Es) or a
tropospheric duct (see Photo A). These two modes of propagation are mostly
summertime phenomena in North America. That means we have only two more Es
and tropospheric ducting seasons left for DXing any U.S. NTSC stations.
NTSC is the acronym typically used to describe the standardized transmission of analog color television signals as adopted by the National Television Standards Committee. The NTSC standard is used in the United States, Canada, some of the other Americas, and in Japan and some other Asian countries. Television stations that broadcast their NTSC signals on the VHF and UHF channel allocations in the United States are required by the FCC to switch their transmissions to a digital standard. This digital method of television broadcasting is known as High-Definition Television, or HDTV.
NTSC TV DXing is the exciting attempt at “catching” and viewing the analog broadcasts on TV Channels 2 and higher from distant stations. During moderate-to-intense Es activity, it’s possible to receive VHF signals from stations hundreds of miles away. Using a beam antenna with some gain, you may be able to see TV station broadcasts on the low-VHF channels, if you don’t live near a TV station in your area broadcasting on the same channel.
TV Channel 2 is quite popular since it’s at
the lowest VHF frequency of all TV channels. Just imagine viewing the
broadcast of a TV station from across the United States, such as the
signal Pat Dyer of Texas captured of the North Dakota TV station KDIX, now
KXMA (see Photo B). He has a website dedicated to this activity at http://home.swbell.net/pjdyer/.
In the last few months, we’ve been exploring
some of the components of a radio signal path and we’ve touched on the
ionosphere. As you might remember, one of the layers of the ionosphere is
the E region, the lowest of regions. Under the right conditions, very
dense clouds of ionization develop that may become so dense and large
(several miles in diameter, for instance) that they refract VHF radio
signals. This is what causes Es propagation.
The ICOM SSB Cut-Out Cure For Boaters
by Gordon West, WB6NOA
August is time to be out of doors, and on the water if you’re lucky enough to own a boat. So this month, we’ll be looking at a marine radio that also operates on the ham bands. The ICOM IC-M802 marine single-sideband transceiver is now in its fourth year of production, and it holds a whopping market share lead over competitors Furuno, JRC, SGC, Raymarine, and SEA. It’s the first marine SSB transceiver for under $1,995 to include full Digital Selective Calling (DSC) emergency, red button capability, and a simple tie-in to an onboard GPS data stream.
Add to the M802’s DSC capability its built-in
separate DSC scanning receiver with digital signal processor chip
(designed for internal filter settings for narrow bandwidth signals when
operating email) and you’ve really got something to talk about. The head
is fully remote and waterproof, with a big bold amber display for
frequency, channel, or alpha-numeric channel names, and full computer
control with its included DIN and RS-232 C connectors.
When the M802 first hit the shelves, sailors
were all set to take advantage of the “one touch email button” for quick
access to the pre-programmed email frequency list. First surprise: email
providers, like marine SailMail and ham radio AirMail, required an
additional external $999 modem, allowing the equipment to run lightning
fast Pactor III signaling to send and receive emails all over the world.
From the beginning, I found the M802 feeble on average voice transmit output. While you could whistle for 150 watts on an oscilloscope, you would only see 100 watts peak on a professional Bird wattmeter. And as you talked and gave your local weather conditions, the thru-line wattmeter would amble in the 20- to 40-watt region. Close talking the noise-canceling mic and raising your voice would help. An early-on control head, SMT (surface-mount technology) chip removal squeaked out a few more watts, but power output compared to an original ICOM M-700 was noticeably less.
Also, a peculiar cut-out problem was associated with running the radio on certain bands, first documented by SSB experts Don Melcher, Shea Weston, and Gary Jensen on the East Coast. This clipping problem was attributed to a likely intermittent antenna connection to the backstay, or a ground fault somewhere in the bilge ground foil run.
Responses to repeated letters and phone calls
to ICOM America suggested that the high-modulation power peaks were
clipping because an element in the antenna system or ground system was
breaking down with the increased high-frequency currents in the
Severe Weather Scanning, Before And After
by Ken Reiss
Severe weather can approach without warning,
and with disastrous consequences. The hurricane season is upon us, and if
you live in areas that can be affected, you probably already keep an eye
on the weather forecasts. But large storms aren’t the only thing to be
aware of, as events of the past year have demonstrated. Severe
thunderstorms, often with straight line winds or tornados embedded in
them, flash flooding, and not-so-flash flooding—even winter event—can have
a major impact on areas large or small.
The scanner shouldn’t be your priority if a
weather event is likely to hit or has hit your area and your house
directly. Then it comes down to how good your overall emergency
preparations are and what kind of damage has been done. The scanner might
be able to keep you better informed of what’s happening in the area and
how widespread the damage might be, but it’s not going to actually help
with anything more pressing. Focus on the things that need to be done
first: first aid for people and animals, food, water, shelter, heat, and
clothing. If you have batteries to spare, power up the scanner, but if you
need them for flashlights, don’t worry about listening. You won’t hear
that much that will really help anyone, although it may put you at ease to
be better informed.
If it’s close by, but you’re not directly
affected you have the luxury of being able to do more. You might help by
volunteering in rescue efforts, or through one of the national agencies
that deal with disaster relief. You might also want to do a little
listening to get a feel for the situation and how widespread the problem
A lot of what’s interesting in an emergency situation is boring as all get out the other 364 days of the year. Here’s where a scanner with lots of banks comes in handy, or even multiple scanners. A computer-controlled or computer-programmable radio would also be convenient so you can have those seldom used, but highly interesting, frequencies ready at a moment’s notice.
The trick with scanning an event, just like
disaster preparedness overall, is to be ready before it happens. Once the
event happens, you won’t have time to look up and research frequencies
that might be in use. A little advance planning goes a long way. Perhaps a
notebook or a word processor file on your computer dedicated to several
types of emergencies might come in handy. When something happens, pull out
the list and start programming. Of course, a computer program that was
pre-loaded with banks would be faster…if you’re prepared ahead of time.
The GRE PSR-500 Advanced Digital Scanner
A Brand New Scanner From A
Familiar—But Newly Independent—
by Rich Wells, N2MCA
As I write this, the 2007 Dayton Hamvention has just concluded its first day of activities and word is spreading among the scanner ranks that there’s a new player in town. Well, sort of. Known for many years as a respected OEM manufacturer of various scanners for RadioShack, GRE is now striking out on its own! Just introduced (along with five other models), the new PSR-500 Advanced Digital Scanner, GRE’s latest high-end handheld, is poised to set a new standard in the technologically complex arena of trunking scanners.
I was given a chance to test an early pre-production unit (which may or may not resemble what is actually shipped), but, unfortunately, I had less than two weeks to play with it before turning in this review.
The design team, which also developed the PRO-96, started on the PSR-500 from scratch with the goal of making it the most powerful scanner ever offered by GRE, while also placing great emphasis on ease of use. An all new, more powerful central processing unit (CPU) was selected and, more importantly, both the CPU and digital signal processor (DSP) will be firmware upgradeable by end users.
The PSR-500 covers 25–54, 108–174, 216–512, 764–824, 849–869, 896–960, and 1240–1300 MHz. On the conventional side of things, it can receive in AM, FM, and Narrow FM modes, decode both CTCSS and DCS and make frequency steps of 3.125, 5, 6.25, 7.5, 8.33, 10, and 12.5 kHz.
In the trunking realm, it can handle Motorola (VHF/UHF/700/800/900 Analog/P25), EDACS (Wide/Narrow/SCAT), and LTR. A new addition is the ability to decode and “squelch” on P25 Network Access Codes (NAC), helping users to more precisely direct their listening to intended targets only. Like the PRO-96, the PSR-500 continues to use GRE’s exclusive automatic adaptive digital tracking and AGC functions to provide the best reception of digital signals.
Memory consists of 1,800 locations built
around a dynamic model that constructs lists as you program them so you
are no longer restricted by fixed bank and channel arrangements. The
PSR-500 also comes with 21 Virtual folders, each one of which can hold the
entire memory contents for later retrieval.
The PSR-500 is almost identical in size to the PRO-96, but just a smidge shorter. The 34-key keypad integrates some new touches, including three “softkeys” underneath the LCD that are used to select options provided on the bottom row of the LCD.
Another new element is the round five-way selector key. It consists of four directional arrow keys surrounding a central select button. Get the hang of this key since it’s what you’ll be using to navigate the menu system and memory contents. The design team stated that one of their goals for user interaction was the ability to manipulate the PSR-500 with just one hand.
Both the keys and the LCD have a brilliant
amber backlight that must be seen to be appreciated. And the menu system
allows you to select whether the LCD, the keypad, or both are illuminated!
SWIFT FX Professional Weather Tracking Software
by Bob Josuweit, WA3PZO
“This will be no Katrina,” read a simple
statement on the Wichita Eagle website following a devastating EF5 (from
the Enhanced Fujita scale, a measurement of storm strength) tornado in
Greensburg, Kansas. The storm erased the town with its 200-mph winds and a
1.5-mile-wide path that racked over 22 miles. The statement was made by
U.S. Senator Pat Roberts (R-KS) as he spoke to a group of residents
staying at a local shelter. Luckily, early warnings reduced the loss of
Now you have the ability to monitor local weather radar, spotter reports, National Weather Service (NWS) watches, and warnings as they happen for any point in the United States.
SWIFT WX Professional is an automated Internet downloading and GPS integration tool written for storm chasers, storm spotters, and emergency management personnel.
If you have an Internet connection, you can use SWIFT WX. The new software for consumers allows them to stay ahead of deadly weather and keep their families protected with advanced warnings—even before the weatherman makes public announcements.
SWIFT WX, which was designed for consumers by tornado chasers, features more than 1,100 weather maps, weather radar down to the street level, GPS tracking, perimeter alerts/first alerts, and up-to-the-minute data feeds from 140 weather service offices. The software allows you to track your position over any weather map by plotting your current position over radar, satellite, or surface maps using GPS technology. If you’re a storm chaser you’ll know where the storm is and how to intercept it.
With SWIFT WX’s storm-tracking technology, you’ll be able to see the path of severe storms, including thunderstorms and tornadoes, on any weather map, indicating bearing, intensity, and velocity. You can also drill down into storm data, viewing reporting stations, cell ID, direction, speed, and other important variables.
According to the developers SWIFT WX is geared
for storm chasers in pursuit of severe weather, spotters observing and
reporting, and emergency managers acting with safety in mind. Using
predefined catalogs, users can download only the pertinent weather data
without browsing through pages of irrelevant information. Users can also
animate a time series of maps to view a storm’s progression.
Everyone talks about the weather, but few people understand it. Have you ever wondered why thunderstorms form? Now you can be the person others come to with a question on the weather. Whether or not you’re a seasoned meteorologist or simply someone interested in studying weather, you should know that the SWIFT WX support staff participates in a users’ forum where questions can be asked and suggestions offered for new features.
For instance, one feature being developed by a
user is an overlay map showing various radio frequencies in use in a given
area. These can include NOAA weather radio frequencies as well as amateur
radio repeaters and SKYWARN frequencies. In fact, the software user
community regularly contributes its own modifications to the program. One
user created a light pollution background map, as well as a tornado map,
showing activity from 1985 to 2004.
UTILITY COMMUNICATIONS DIGEST
Utility Monitoring Without “Infrastructure”
by John Kasupski, KC2HMZ
August in the northern hemisphere is, generally speaking, a wonderful time of the year when outdoor activities are at the top of everyone’s “To-Do” list. Wash the car. Mow the lawn. Put up that new antenna, or perform maintenance on our existing ones. Maybe take in a baseball game (even though the weather warmed up a few months ago, the pennant races are just beginning to heat up).
But, ah yes...the weather. In August in the “top half” of the world, it’s usually pretty nice—but not always. Sometimes we just get a rainy day or two. That might be a good time to fire up your radios and have some fun (if there’s no lightning in the area), because you have the perfect excuse to stay indoors. On the other hand, there are those nasty thunderstorms and tornadoes to worry about, and August is also most definitely in hurricane season. No, sometimes the weather in August just isn’t as nice as we would like; in fact, it can get downright destructive!
Fortunately, nasty summer weather doesn’t always destroy everything in sight. It does, however, often present some minor difficulties (although they may not seem minor at the time) for a few days. Often, it doesn’t take a hurricane or tornado to knock down power lines, the high winds that accompany some thunderstorms can easily do this. Lightning from a typical thunderstorm might strike a nearby transformer. So, the storm moves away, the lightning and high winds vanish, leaving their destruction behind them, and you must wait several hours for the local utility companies to deal with the resulting damage to the local power grid. You don’t really want to go outside because everything’s just been drenched by rainfall—even your favorite patio lounge chair has an inch of water on top, right where you sit.
You’re stuck inside, with no electricity. What
to do? If you’ve prepared for such an eventuality in advance, you know
exactly what you’ll do. You’ll do just what I said two paragraphs ago:
fire up your radios and have some fun!
In order to prowl the shortwave bands in search of nifty utility catches to add to our logs, we basically need three things: our receiver, a suitable power source for the radio, and, of course, an antenna. If you’ve chosen wisely when acquiring the radio, you’ll have one that not only meets the technical requirements of a good receiver, but also one that gives you a few different options for providing the rig with electrical power. This means that if the radio has its own built-in power supply and is designed so that you can simply plug it into an AC wall outlet, it will also have some provision for using DC power instead so you can run it on either internal or external batteries when AC power is unavailable.
Of course, if your radio doesn’t have its own internal power supply and is designed to be run from an external power supply that converts AC house current to DC, then your rig is already set up and you simply need to provide an alternative to the power supply you normally use with the radio.
The best source I’ve found of alternative
power for radios is the typical deep-cycle marine battery, widely sold in
discount department stores as well as specialty stores that cater to
boaters. I’ve seen these batteries power a 50-watt mobile VHF transceiver
for a couple of days during emergency use, and a typical 100-watt ham
transceiver for several hours during a contest, when the radio was being
used to transmit almost as much as to receive (transmitting uses much more
power than receiving). If you’re only going to listen, the battery will
last even longer.
Capitol Hill And FCC Actions Affecting Communications
by Richard Fisher, KI6SN
APCO Homeland Security Course Cited In 9-1-1 Magazine
An article titled “Homeland Security Training for Dispatchers” was published in the May issue of 9-1-1 Magazine, citing the importance of telecommunicators and their training, according to a news release posted on the website of the Association of Public-Safety Communications Officials (APCO), International.
“In the article, author
Mike Scott mentions the APCO Institute’s Telecommunicator’s Role in
Homeland Security course and the critical role dispatchers play in
recognizing terrorist incidents and how this course will assist the
telecommunicator in determining that a possible terrorist event has
occurred and the appropriate response,” the organization said.
“Adequate access to the radio spectrum and the ability to install and operate effective amateur radio stations” have been adopted as the basis for key legislative initiatives for the American Radio Relay League during the 2007–2008 110th Congress, the organization has announced.
The League, which
represents thousands of radio amateurs nationwide, said that the “ability
for the amateur radio service to maintain and expand its benefits to the
public” rests on frequencies and reasonable antennas, “two key elements of
More Morse Madness
by Bill Price, N3AVY
It’s no secret among my friends and my readers that I like CW (or Morse code, or dits and dahs, or dots and dashes) and I always have, even from the days before I knew all the letters, numbers, and symbols. And I have to admit, I was both excited and nervous when I was accepted to the U.S. Coast Guard Radioman “A” School in Groton, Connecticut, right out of boot camp in 1966. Granted, it took a certain demonstrated aptitude for copying Morse code and other communication talents to be accepted, but the “wash-out” rate was fairly high, and was usually among those who just couldn’t copy “the code.”
And copying “the code” didn’t just mean you learned that “A” was “didah.” No, not by a long shot. You had to know all 26 letters of the alphabet, all 10 numerals, period, comma, colon, semicolon, dash, slant bar, open quote, close quote, open parenthesis, close parentheses, apostrophe, and the combined op signs of BT AR AS VA (SK), which were sent as one group.
Oh, and the elusive dollar sign. Yes, there really is a symbol for the dollar sign: DS, sent as one group. Gets you every time.
There were also the Q-signals, known well to hams and commercial civilian CW operators (no longer in existence), such as QRV (“I am ready; go ahead”) and QRN (“Natural noise, like static”) or QRU IMI (“Who is calling me?”). In addition to those, and there were quite a few that were used more in military and commercial communications than in ham radio, such as the Z-signals, which were used exclusively by the military.
Here’s a funny story that sprang from the Z-signals in the Bermuda triangle. It had nothing to do with ships disappearing but instead with some miscommunication, even with the most concise signal system devised.
A navy ship’s radioman had called a Coast Guard ship’s radioman (using CW) and asked,
“What are the broadcast stations in Bermuda—we want to tune the rec-deck radios to them.”
The CG RM replied simply, “ZBM1 and ZBM2.”
You should know that ZBM1 means “put on a qualified operator” and ZBM2 means “put on a qualified speed-key operator.”
The navy ship waited, and another operator took over and said, “I am ZBM1 and ZBM2, now what are the broadcast stations in Bermuda?”
The CG RM again replied, “ZBM1 and ZBM2.”
There was a long pause from the navy ship, then another operator came on and said, “THIS IS MASTER CHIEF RM so-and-so, I am ZBM1 and ZBM2, now cut out the nonsense and tell me what the broadcast stations are in Bermuda or I’ll contact your bridge and have your communication officer take disciplinary action against you!”
The CG RM replied, “Hi, Chief. The callsigns of the only two broadcast stations in Bermuda are ZBM1 and ZBM2.”
I understand that the radio shack crews of both ships met in Hamilton, Bermuda, and had a few drinks together.
Once you learned all these symbols, you had to
learn to copy them, and not with a pen or pencil, but on a typewriter. Oh,
did I mention that the typewriter had all blank keys? Yes, it helped if
you knew how to touch type before you go there, otherwise you had two
things to learn at the same time.
I know so many would-be hams who say they
could never quite get the code. I also know many hams who only got the
code by years of determination against what seemed to be “Morse Dyslexia”
or something like it, and an awful lot of people using computer keyboards
today once told me they couldn’t possibly learn to touch type.
“Learn the code; learn to type—or learn to
cook breakfast for those who can.”