TUNING IN (PDF)

 

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NEWSWORTHY

Unwired

The Weirder Side Of Wireless

by Staff

 

With Mumbled Directions Home

If, like a rolling stone, you find yourself skittering clueless down an unknown road, it just may be because Bob Dylan is guiding you home. According to a report in the Washington Post, among other sources, Dylan said on his BBC satellite radio program, Theme Time Radio Hour, that two carmakers have expressed an interest in borrowing (I guess “renting” is a better choice) the famous raspy-mumbly voice. Rumor has it he’s negotiating with two car manufacturers to be the voice of their in-car navigation systems.

Personally, I’ve always only been able to understand about every third word of the once-counter-culture figure, and am not sure I’d want to put in the effort required to decipher his instructions for high-speed merging. Dylan didn’t put such anxiety to rest by giving a teaser of his guiding ability on his radio show, previewing his would-be GPS vocals with, “Left at the next street. No, right. You know what? Just go straight.” Subsequent reports from a number of sources have said that Dylan meant it as a joke. We’ll see. Be on the lookout for cars having trouble with high-speed merges.

Madonna Needs To Watch Her Language

A Bulgarian radio station was fined for running a pre-recorded message from Madonna, inviting fans to her concert in Sofia, Bulgaria’s capital. The problem was not with her music, clothing, or controversial projects and behavior, but that she used English to record the message. Bulgaria’s Council for Electronic Media slapped Darik Radio with a large fine for airing Madonna’s English invitation, according to the Bulgarian daily, 24 Chasa and The Sofia Echo website. Apparently chapter 12 article 1 of the Radio and Television Act states that all advertisements in foreign languages are forbidden, so the commission ordered Darik Radio to pay a penalty in the range of 2000 to 15000 leva (approximately US $1,445–10,838). A repeat of the offending broadcast would have doubled the fine. The 10-second message from Madonna to her fans in Bulgaria said: “Hello Bulgaria, this is Madonna and I expect to see you at the August 29 show in Sofia in Vassil Levsli Stadium.”

The Sofia Echo stated that a spokesperson for Sofia Music Enterprises, the Bulgarian organizers of Madonna’s concert, said “this is normal procedure and it is used in all countries. Any time Madonna has a concert in a country, she records a message for her fans, and it is always in English. There is no way that an exception will be made just for us.” Konstantin Vulkov, program manager of Darik Radio said the station “apologizes that Madonna is not proficient in Bulgarian,” according to The Sofia Echo report.
 

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NEWSWORTHY

InfoCentral

News, Trends, And Short Takes

by D. Prabakaran

 

RFI Signs Mobile Broadcast Deal For Five U.S. Cities

Radio France International has signed an agreement with mobile phone broadcaster AudioNow to broadcast its French programs on the telephone network, 24 hours a day, in five US cities. Listeners in Boston, Chicago, San Francisco, Miami, and New York will be able to hear RFI on their cellphones by calling the following phone numbers (only local charges will apply): 617-963-1545 (Boston), 312-646-7684 (Chicago), 415-200-0603 (San Francisco), 786-228-5543 (Miami), and in New York City (number not provided at press time).
(Source: RFI)

BBC Russian Launches Online Archive Of Key Historical Radio Moments

The website of the BBC Russian service (bbcrussian.com) launched an archive of significant historical radio programs from the past 45 years. Among the voices featured in the audio archive are Alexander Kerensky, Prime Minister during the 1917 Russian Revolution; Nobel Laureates for Literature Alexander Solzhenitsyn and Joseph Brodsky; one of Russia’s great poets Anna Akhmatova; and Stalin’s daughter Svetlana Alliluyeva. It also features former British Prime Minister Margaret Thatcher, and former Beatle Paul McCartney, both of whom took part in live phone-ins with audiences in the USSR in the Eighties. The archive can be accessed through the radio page at www.bbcrussian.com
(Source: BBC World Service)

Taliban Launch New Propaganda Mouthpiece In Southern Afghanistan

Taliban insurgents fighting Afghan and international troops based in Afghanistan have established their propaganda mouthpiece in the southern Ghazni province, locals said. The FM transmitter, according to locals, airs programs from 7 p.m. until 9 p.m. (1430–1630 UTC) local time and often broadcasts Taliban anti-government propaganda in Pashtu. It has identified itself as Da Shariat Ghag Radio, or Radio voice of Sharia (Islamic Laws) and has been airing programs on Taliban anti-government activities, according to one local. Da Shariat Ghag Radio was the official mouthpiece of Taliban regime before its collapse in late 2001. Taliban purported spokesman Zabihullah Mujahid told media from an undisclosed location via telephone that militants have established four radio stations in the country.
(Source: Xinhua)
 

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NEWSWORTHY

Washington Beat

Capitol Hill And FCC Actions Affecting Communications

by Richard Fisher, KI6SN

 

FCC Takes Plunge Into Social Networking And Blogging

In an effort to achieve an “open and participatory process,” the Federal Communications Commission took a technological leap in mid-August when it created its identity on the social networking site Twitter and started an Internet blog focusing on the National Broadband Plan.

Twitter allows users to post text-based messages of up to 140 characters displayed on the originator’s profile page and delivered to site subscribers. In its infancy, the Commission’s Twitter page had already attracted almost 2,000 followers. The site can be found at http://twitter.com/fccdotgov.

The FCC has also started an Internet blog called “Blogband,” focusing on the National Broadband Plan. It can be accessed at http://blog.broadband. gov/. “Like our unprecedented two-dozen public workshops and the (scheduled) public hearings, Blogband is part of the FCC’s commitment to an open and participatory process,” FCC Chairman Julius Genachowski said in Blogband’s inaugural posting. The information “will keep people up-to-date about the work the FCC is doing and the progress we’re making. But we want it to be a two-way conversation.”

Genachowski pointed out that in the Commission’s opinion, the “National Broadband Plan is one of the most important initiatives that the FCC has ever undertaken…What better time to start blogging than now?...we need as many people involved as possible.”
Comments to the blog are monitored during business hours and reviewed before being posted, the FCC said.

Radio Amateur Vanity Callsign Fees Increased

Amateur radio operators who request callsigns from the FCC’s vanity pool are paying $13.40 for the privilege following a rate hike that took effect September 10. In August, the Commission announced it would increase the vanity fee from $12.30 to $13.40—a hike of $1.10. It was the second consecutive year for rate increases in the program.
“The FCC is authorized by the Communications Act of 1934, As Amended, to collect vanity call sign fees to recover the costs associated with that program,” according to a news release posted on the Web by the American Radio Relay League. “The vanity call sign regulatory fee is payable not only when applying for a new vanity call sign, but also upon renewing a vanity call sign for a new 10 year term.

“The notice in the August 11, 2009 Federal Register, entitled ‘Assessment and Collection of Regulatory Fees for Fiscal Year 2009,’ includes regulatory fees; these fees are expected to recover a total of $341,875,000 during FY2009, encompassing all the services the FCC regulates,” the ARRL reported.
 

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Newsworthy

Horizons

Sunspots Anyone?

by Rob de Santos

 

Back in the early ’80s, the singer/songwriter Sting wrote lyrics, “There’s a little black spot on the sun today. It’s the same old thing as yesterday.” Has it been a while since you had that experience? For many readers I suspect it’s your private kingdom of pain under current solar conditions.

One of the facts of life for every shortwave listener and ham of my generation concerns the sunspot cycle: Once you had any experience in the hobby, you just knew that as sunspots increase, the propagation improves (or changes), and as they wane, reception worsens, and then the cycle repeats. Except when it doesn’t. Few readers of this magazine will not be aware of how slow the upside of this new solar cycle seems to be.

But what if the sunspots don’t return? Or at least, they return in such small numbers we never have a normal “peak” to the solar cycle, then what? The implications for the communications business are significant and not just in a hobby sense. Sunspot levels affect far more than just the reception of Radio Australia in my bedroom. Let’s consider just a few of the ways that might change communications:

Satellite lifetimes: Orbits don’t decay as quickly when solar activity is lower, and the risk of damage to sensitive electronics is reduced when there are fewer solar storms. This would mean satellites wouldn’t have to be replaced as quickly and it would reduce the decay rate of their orbits. This would affect everything from television relays to the lifetime of amateur radio’s “OSCAR” satellites.

Weather. This is a big gray area. We know that the sun impacts our terrestrial weather and longer-term climatic conditions. The problem is we don’t know just how much. Past periods with low sunspot numbers over decades corresponded to cooler worldwide temperatures. It’s hard to say how, when combined with “global warming” this would change communications habits around the globe.
 

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The Technology Of Modern Rebellion

Text Messaging And Twitter Vs. Repressive Regimes

By Kirk A. Kleinschmidt, NTØZ

 

As everyday people in ordinary neighborhoods, across the 50 states and from continent to continent, strive to better themselves, raise their children, and go about their daily lives, the world they live has been growing ever smaller. Over the past 100 years the relentless march of technology—radio, electronics, computers, the Internet, and telecommunications—familiar to Pop’Comm readers, has been a blessing to society as a whole, but a curse to individuals, corporations, and governments with “things to hide” or opposing issues to suppress.

From celebrities frolicking on a secluded South Pacific beach (snap!—the paparazzo’s digital photo is uploaded to a Hollywood tell-all Internet tabloid via cell phone or sat phone and, in less than three minutes, is online for everyone to see); to cell phone video of the hanging of former Iraqi dictator Saddam Hussein (which even the U.S. wanted to suppress) and the murder, on June 20, 2009, allegedly by Iranian government agents, of 26-year-old Neda Agha-Soltani, a young Iranian woman who was shot dead as she stepped out of her car in Tehran near the site of an anti-government protest (the graphic and unedited cell phone video of Soltani’s last moments spread like wildfire on the Internet and global TV news shows and became a rallying event for Iranians protesting the questionable election victory of President Mahmoud Ahmadinejad); it’s almost impossible to suppress information and events in the modern era of entrenched interconnectedness.

Upheaval In Iran

Although this article primarily focuses on the tools and techniques used by the citizens and the government of Iran during the events associated with the country’s contested presidential election in the summer of 2009, the discussion is relevant to many events in many other countries, including Iraq, Afghanistan, Myanmar, China, and even the U.S. and other “developed” nations—and it will likely become even more relevant in the near future.

Although Iranian citizens enjoy certain “democracy-like” freedoms and educational opportunities not necessarily enjoyed by other Islamic republics in the region, Iranian citizens—especially an ever-more-strident youthful demographic—had grown increasingly unhappy with the country’s elected and theocratic leaders.

This general unrest came to a head in the summer of 2009 when, from mid-June through early August, tens of thousands of people (probably more) protested in the streets of Tehran and several other major Iranian cities in support of opposition candidate Mir-Hossein Mousavi.

Amid widespread protests and allegations of massive voter fraud, Ayatollah Ali Khamenei, Iran’s religious leader and behind-the-scenes political power broker, declared that President Mahmoud Ahmadinejad had won a decisive reelection victory and that the election’s dramatic result was a “divine assessment.”

Outside Iran’s inner political circle the divine assessment seemed all too profane. Many citizens and all of the opposition presidential candidates, including Mousavi, claimed that the election was manipulated and that the results were rigged. Although foreign election monitors were generally not allowed to keep an eye on things inside Iran, most outside observers side with the Iranian opposition in noting “electoral irregularities.” The protests that followed have been called “The Green Revolution” (playing on Mousavi’s green campaign colors) and “The Persian Awakening.”
 

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BROADCASTING

Broadcast Technology

Exploring The World On A Radio DXpedition

by Bruce A. Conti

 

Since the famed 1991 Newfoundland DXpedition celebrating the 90-year anniversary of the historic first Marconi transatlantic wireless communication, the DXpedition has become an integral part of AM broadcast band (or mediumwave) long-distance listening (DXing).

Here in the Northern Hemisphere, November is considered one of the best months for DXpeditions, so we dedicate this month to all who have braved carrying suspicious radio gear through airport security, erecting antennas over rough terrain in foul weather, and explaining the CIA-like activity to innkeepers, curious passers by, and sometimes local law enforcement.

Such are the risks we DXpeditioners take to catch an elusive signal, add a country to the logbook, or receive signals that could never be heard at home. Five representative DXpeditions out of many solo and group sessions held over the past year have been chosen to try to capture the DXcitement. Narratives of the DXpeditioners are followed by selected logs. All times are UTC.

Cape Point, South Africa

Many a DXer has dreamed of a South African radio safari. The southern tip of Africa is an outstanding region for DXpeditioning due to Atlantic and Indian Ocean saltwater paths. Fortunately for those of us unable to make the long journey to such an exotic locale, we can still enjoy the experience through DXers lucky enough to live in this radio active part of the world. The following report and logs come from South African resident Graham Bell who describes a solo DXpedition:

I spent a couple of nights at Elands Cottage in the Cape Point Reserve, south of Cape Town. It’s a comfortable cottage with lots of space around (for antennas). I put out two Beverage-On-Ground (BOG) antennas, one of 250-m at 310 degrees and another of 320-m at 320 degrees. I also had a shorter 80-m longwire pointing to magnetic north. Though the two BOG antennas were on a very similar bearing but of differing lengths, I can’t say either one was systematically better than the other (front, back or null). What I found was that it was useful to have the option to switch from one to the other to fine tune the incoming signal. In some cases they gave very different results. I used both my Drake R8 and NRD-545. The Drake hasn’t had many outings in recent years so it was a good chance to be reminded of what a good receiver it is, especially in the quiet conditions we enjoy in these parts. Highlights were a fair signal from XEPE San Diego, two Philippines stations and “local” stations Emissora Provincial de Bengo, Angola and Radio Benue, Makurdi, Nigeria. The AM dial used to be peppered with Angolans, Cameroonians, and Nigerians but there aren’t many left. These two came in with really fine signals and audio with interesting local programming, especially Makurdi.

590 LS4 Radio Continental, Capital Federal, Argentina, at 0557 Spanish panel discussion, IDs; good signal.
594 Federal Radio Corp. of Nigeria, Kaduna, Nigeria, at 1920 chants parallel 6089.84 kHz; good.
729 5RN Adelaide, Australia, at 1530 heard with ABC news; good.
801 AIR Jabalpur, India, at 1734 news in English; fair.
820 Radio Paradise, St Kitts & Nevis, at 0305 U.S. preacher; fair.
850 WEEI Boston, Massachusetts, at 0548 mentioned website, “WEEI dot com,” fair.
 

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IN GEAR

Power Up

New, Interesting, And Useful Communications Products

by Staff

 

MFJ Enters Scanner Market With Two New Offerings

MFJ has entered the scanner market with two new product introductions: the MFJ-8310 Base Scanner, which receives NOAA, police/fire/ham repeaters; and the MFJ-8322 Analog Trunking Scanner, a handheld model that also tunes 800-MHz public service bands and analog Motorola (type I, II and hybrid), EDACS Wide and LTR trunked systems.

The MFJ-8310 scanner monitors 2-meter, 70-cm, 10-meter and 6-meter repeaters plus repeater inputs and local simplex frequencies, NOAA weather broadcasts, weather alerts, SKYWARN, VHF and UHF business bands, commercial aircraft, marine band, FRS/GMRS frequencies and more. During severe weather, its one-touch weather button takes the place of expensive single-purpose weather radio; another one-touch button monitors SKYWARN trained weather observers (requires one-time programming). It features a BNC antenna connection; backlit LCD and 3-inch speaker; front panel on/off switch with separate volume and squelch controls; and 3.5-mm headset jack for private listening. It includes pull-up BNC antenna and 120 VAC-to-9 VDC adapter.

The MFJ-8322 is a triple-trunking handheld scanner with alpha display that lets you easily program talkgroup IDs. Covering all the UHF and VHF bands, it offers the same features as the MFJ-8310 base scanner and adds the 222–225 MHz ham band, military aircraft frequencies, and the 1240–1300 MHz ham band. It stores up to 1,000 frequencies, a maximum of 10 trunked systems and up to 1,500 total TIDs. A Spectrum Sweeper mode offers remarkable sensitivity and rapidly searches for local transmitters of unknown frequency, finding, tuning, and monitoring a nearby transmission in roughly 3/4 of a second, or you can lock out undesired frequencies and search again.

Other features include PC programming capability (the MFJ-5432 Scanner USB cable connects the scanner to your PC; $29.95) and BNC antenna connector. It also comes with a flex antenna and AC adapter charger (requires four AA Alkaline or NiMH batteries; NiMH charge automatically to full charge in the scanner when the adapter/charger is attached), on/off/volume control and squelch control, and 3.5-mm headset jack.

The MFJ-8322 retails for $199.95; the MFJ-8310 for $99.95. For additional information, to order, get a free catalog, or for your nearest dealer, contact MFJ Enterprises, 300 Industrial Park Road, Starkville, MS 39759; Phone: 800-647-1800; Web: www.mfjenterprises.com.
 

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THE PRACTICAL SIDE

The Antenna Room

TV Antenna Basics

by Kent Britain, WA5VJB

 

I’ve often enjoyed reading the TV channel history of a city just by looking at the rooftops as I drove though the neighborhoods. By understanding the different antenna designs, like the one in Photo A, you can tell what channels the people wanted to watch over the decades. Well, so much for history…now onto modern times, like why a good understanding of TV antennas is handy when you need to put one up. Let’s take it from the beginning, with television frequency ranges, as follows:

VHF Lo TV Ch 2–6 54–88 MHz
VHF Hi TV Ch 7–13 170–216 MHz
UHF TV Ch 14–83 470–890 MHz
(1940–1982)
UHF TV Ch 14–69 470–806 MHz
(1980–2009)
UHF TV Ch 14–51 470–696 MHz
(Present)

We start with the three main U.S. Bands for TV transmitters. TV Channels 2 to 6, 7 to 13 and 14 to 51. On most antennas there are elements designed to resonate in each of these three frequency bands. The antenna can then be used just about anywhere to watch any channel.

Let’s take a look at the conical, sometimes called bi-conical, TV antenna in Figure 1. When hams used them they were called “wonder bar” antennas, and if you see one of these in the air, you’ll know that it’s been there for half a century. They’re pretty good on VHF Lo, and the short elements in the middle are for VHF Hi. When these were first designed, the UHF band wasn’t even around. My first ham 6-meter antenna was one of these, but I extended each element about 6 inches. Hey, I worked eight states on 6-meter AM with it! It also worked well on TV Channel 1, but more on that at the end of the column.

Now we move on to the typical herringbone TV antenna in Photo B. About 40 years ago it was discovered that if you swept the log periodic antenna elements forward at about a 30-degree angle, the log periodic worked well on its third harmonic. So if the log periodic on the left in this figure were designed to cover 50–100 MHz, then the log periodic on the right would work on 50–100 MHz and 150–300 MHz. The third harmonic of 56–88 MHz is 168–264 MHz and covers the 170–216 MHz VHF Hi band nicely. A swept forward log periodic, therefore, can easily cover both VHF Lo and VHF Hi at the same time, and that’s why so many outdoor TV antennas use this basic design. On the front you see the UHF elements which we’ll cover a bit more in a moment.

Three elements in the herringbone log periodic is about the smallest you can make work on both VHF Lo and VHF Hi. But there is no upper limit on this antenna: As you add more elements, gain and size goes up. About a dozen VHF Lo elements is the practical limit and that would be nearly 30 feet long. (One of those “round-to-it” projects on my work bench is a 140–170 MHz herringbone log periodic to cover 140–170 MHz and 420–500 MHz for both the scanner and ham crowds in one antenna.)
 

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THE INTERSECTION OF

COMPUTERS AND RADIO

RF Bits

Internet Radio Roundup: A Sampling From The WiFi Scene

by Dan Srebnick, K2DLS

 

Ever since Real Audio hit the scene in 1995, I’ve been intrigued by online “DX” possibilities. I started out listening to a lot of Dutch domestic stations that simulcast on the Internet (the Dutch were early adopters of Internet radio). The World Radio Network (wrn.org) offered the opportunity to listen to international broadcasters such as Radio Nederland and the BBC. Early listening sessions consisted of 16 kpbs streams over a 28.8 kbps dialup. Windows 3.1 crashed a lot, making online listening sometimes as much of a challenge as “real DX.”

A lot has changed. Today, broadband Internet connections are common in many households. Windows is stable, and Mac OS/X and Linux all offer media players to tune into Internet media content. But the biggest change over the past couple of years is that a computer is not needed to listen to radio via the Internet. Today, we have “WiFi radio.”
WiFi radio first came on the scene about three years ago. A WiFi radio is a dedicated appliance for receiving Internet radio and media content. It connects to the Internet using an 802.11-type wireless connection or a hardwired Ethernet cable. It has a radio-like human interface, generally consisting of a small text display—the “dial”—and some knobs and buttons. Some have remote controls and one-touch memories to recall favorite stations. Some have internal speakers and others allow one to connect to a good quality stereo or surround sound amplifier.

The major differentiator between the different models of WiFi radio are the chipsets. The chipset includes firmware that provides the radio’s operating system. The operating system determines the “personality” of the device, defines its features and how you interact with it. While it sounds a lot like a computer, the similarity ends here as there is no keyboard, mouse, or hard disk involved.

A WiFi Sampler

The major WiFi radio platforms fall into the following categories:

Reciva (<www.reciva.com>)—Supports Real Audio, MP3, WMA, AAC, AU, WAV, and AIFF formats. Originally, only Reciva supported Real Audio, used by popular stations such as BBC Radios 1 and 4. These radios run the Barracuda chipset.
vTuner (<www.vtuner.com>)—Real Audio support is reported to have been recently added to some models, making vTuner a capable rival to Reciva. Also supports MP3, WMA, AAC, AU, WAV, and AIFF.

Many different manufacturers offer Reciva- and vTuner-based radios. Logitech (<www.logitech.com>) and Phoenix (<www.com-one.biz>) also have proprietary offerings with full feature sets, and Phoenix seems to have recently added Real Audio, so choose carefully. Each vendor has a website that allows the listener to create lists of their favorite stations and, in some cases, playlists. Let’s take a look at some of the available choices.
 

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PUBLIC SERVICE/SAFETY

EmComm Essentials

Lessons Learned From The “October Surprise”—Simple Preparedness Steps You Can Take

by John Kasupski, KC2HMZ

 

This month I’m going to do a bit of reminiscing about a severe winter weather event that took place in Buffalo, New York, roughly three years ago, in October 2006, with an eye toward relating what can be learned from the standpoint of EmComm and preparedness.

Even if you don’t live in an area that is prone to winter storms, the lessons from one disaster are as good as the lessons from the next. While you may not get serious snow or ice, chances are (unfortunately) good that there’s some sort of natural or man-made disaster you might be subjected to. The results are often similar regardless of the nature of the event: disruption of food and water supplies and communications; interruption of utility service; travel difficult or impossible…the list goes on. How do you prepare for it?

The so-called “October Surprise” of 2006 was an unusual early-season lake effect snowstorm that hit Buffalo and the surrounding area in the U.S. and Canada. It began in the afternoon on October 12, and didn’t end until the morning of the next day. It became known as the October surprise because in Buffalo autumn weather is typically just beginning then. The leaves on the trees were just beginning to turn brilliant colors and boats were still moving along the Erie Canal and the Niagara River. Snow blowers were still stored in garages, their fuel tanks empty. The water temperature in Lake Erie was 62 degrees Fahrenheit. The lake effect storms capable of producing feet—not inches—of snow in just a few hours were still (we thought!) several weeks away at least.

A Surprise That Shouldn’t Have Been

Like most disasters, the October Surprise happened unexpectedly; and yet, it shouldn’t have come as a surprise at all. The first concerns of a possible “Lake Effect Snow Event” were raised on October 6 as medium- and long-range numerical weather models began to indicate conditions would be potentially favorable for lake effect precipitation, resulting in mixed snow-rain conditions. The long-term forecast from the Buffalo office of the National Weather Service indicated possible lake effect snows, but predicted that accumulations would be minimal.

By October 11, the Buffalo NWS and associated weather offices in the U.S and Canada began issuing special advisories for the possibility of lake effect snows, which mentioned that since the leaves were still on the trees, the combination of snow and wet leaves on trees could cause branches or trees to fall, bringing down power lines and resulting in widespread power outages. That’s exactly what happened, starting the following afternoon.

The first notable ground accumulations started to occur just before 5 p.m., and by 8 p.m., reports of downed trees and power lines and other damage began to flood the NWS offices (see Photos A and B). Schools were closed for a week. Telephone lines were still down weeks later. Thirteen people died. The damage was the worst of any storm in Buffalo’s history.

 

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THE PRACTICAL SIDE

The Propagation Corner

A Sunspot Puzzle

by Tomas Hood
 

Something is unusual about the current sunspot cycle. The current solar minimum has been unusually long, and with more than 700 days without sunspots through August 2009, the number of spotless days has not been equaled since 1933 (see <http://users.telenet.be/j.janssens/ Spotless/Spotless.html>). The solar wind is reported to be in a uniquely low energy state since space measurements began nearly 40 years ago. This solar minimum has become a real puzzle to solar scientists who are working diligently to understand what exactly is happening with our sun.

There’s an obvious interest in a lack of sunspots from the perspective of radio hobbyists because solar activity as measured by sunspot counts correlates to the strength of the ionosphere. Without an energized ionosphere, shortwave signals won’t reach around the world. There are other reasons, too, for an interest in this uniquely quiet solar minimum.
For instance, does this solar minimum resemble the lack of solar activity observed during the period from 1645 to 1715, when the sun entered a period of low activity now known as the Maunder Minimum? That was a period of several 11-year periods during which the sun displayed few, if any, sunspots. Models of the sun’s irradiance suggest that the solar energy input to the Earth decreased during that time and that this change in solar activity could explain the low temperatures recorded in Europe during the Little Ice Age. Is this happening again?

About Those Spots

Sunspots are magnetic regions on the sun with magnetic field strengths thousands of times stronger than the Earth’s magnetic field. Plasma flows in the sun’s magnetic field lines (Figure 1), and sunspots appear as dark spots on its surface. Temperatures in the dark centers of sunspots, the “umbra,” drop to about 3700 K, compared to 5700 K for the surrounding photosphere. It’s this difference in temperatures that makes the spots appear darker than elsewhere.

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 “penumbra” (Figure 2).

Since the time of Galileo Galilea, who made the first European observations of sunspots in 1610, observers and scientists have discovered a great deal about the sun and its influence on the Earth and our atmosphere. The Chinese and many other early civilizations were the first to discover sunspots. Daily sunspot observations were started at the Zurich Observatory in 1749, and by 1849 continuous sunspot observations were recorded. Over time, cycles in solar activity were revealed. The sun’s sunspot activity has a cycle that lasts for an approximate 11-year period. The cycle starts with very quiet solar activity with very few sunspots, then peaks about three to five years later with a very high number of daily sunspots, and then decreases in sunspot activity until the end of the solar cycle.
 

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BROADCASTING

Shannon’s Broadcast Classics

“Looking” At Broadcast History:
A Cornucopia Of The Visual Side Of The Radio Hobby

by Shannon Huniwell

 

When my neighbor Melissa heard the news on her kitchen radio, time rushed backwards. She quickly connected the story’s dots and suddenly saw herself in Seattle’s North City School again. A memory crystallized.

Standing there clear as day in her mind’s eye, Melissa’s fourth grade teacher, Mrs. Aguayo, had just explained to the class that they’d be putting messages in soda bottles, and a friend with a boat would toss them onto waves of Puget Sound. Mrs. Aguayo said some could travel to distant shores and predicted that a few might even be found by curious people who’d be happy to respond to the enclosed letter offering a snapshot of the sender if the finder notified the school by mail.

That 1987 science project related to geography lessons and an elementary study of ocean currents netted one response—21 years and 1,735 miles later. “Merle Brandell and his black lab, Slapsey, were beach-combing along the Bering Sea,” the announcer broadcasting Associated Press news copy (from March 23, 2008) informed his audience, “when he spied a plastic bottle...along the shore of his tiny remote western Alaskan fishing village.” Inside the weathered container was the typed form letter signed by a classmate Melissa couldn’t picture.

According to the AP, Brandell wrote to Seattle’s Shoreline School District and a helpful official there tracked down the girl who’d sent the message, “now a 30-year-old accountant...who lives in Seattle. ‘I don’t remember the project,’ she told reporters. ‘It was so long ago. Elementary school is kind of foggy.’”

Melissa’s recollections of the bottle-message project are vivid compared to those of the young woman quoted on the radio. Like my Dad, Melissa’s father is a longtime DXer. Consequently, he had instilled in her a love of sending away for free stuff from radio stations. “Envisioning the little plastic bottle sailing my letter to some exotic port of call,” she said, smiling, “I guess was kind of like taking a fun chance that something even more interesting might come my way.”

Her experience in the DXing hobby taught her the truth of the maxim that you have to give in order to receive. “It was always a thrill to hop off the school bus in the afternoon, run to our mailbox, and see what resulted from reception reports Dad had helped me fire off a few weeks earlier,” Melissa remembered. “My wish was to get a little visual piece of the station I’d heard sail through the air. Whenever the return address sported a station logo, I felt like I’d won the lottery!”
 

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THE PRACTICAL SIDE

The Wireless Connection

AC Voltmeters For Dummies

by Peter J. Bertini
 

I once commented that a diode wired in series in an AC circuit would reduce the power by one half, not the voltage. That is counter intuitive to what you would think at first, but it makes sense once you consider that the duty cycle—and thus the power—has been reduced by 50 percent. That works out to about 0.707 times the RMS voltage, or 81.3 volts for a 115 VAC line voltage.

I was surprised to receive several very adamant admonishments insisting that I was wrong. The truth is that anyone using a typical True RMS voltmeter, which is an AC coupled device, would be misled by a reading that is actually closer to one half the applied voltage than the times 0.707 calculation that is correct for half power. This is most unfortunate, and I believe in doing test bench experiments to verify that things are as they appear. But I found it even odder that the few who complained never bothered to run the math using the power formulas to prove their point, one way or the other.

I believe that when well-intended experiments lead to erroneous conclusions, it is time to act! But I’m getting ahead of myself…

Let’s begin by discussing the ins-and-outs of AC voltmeters. There are plenty of reference books that delve into the mathematics; but I’d rather take a few editorial liberties to keep things simple for those folks who are not engineers or technicians.

Remember that an AC waveform is dynamic and is constantly changing amplitude with time. To determine the power contained in that waveform, the voltage is averaged to a corresponding reading that represents the same energy that would be delivered by a steady-state DC voltage. That AC voltage is the root mean square (RMS) voltage. We should be pretty much agreement that we need accurate AC voltage readings to use the power formulas or Ohms Law.

Averaging Type AC Voltmeters

Vintage, inexpensive shop meters were simple devices, and they assumed that the voltages being measured would most likely be a pure sinewave that was related to the AC line voltage. The AC voltage being measured is rectified in the meter and is really displayed as a DC voltage. The AC meter scales indicate the average of the AC voltage being measured. If the voltage is a sinewave, then the average is the correct RMS voltage; if not, all bets are off.

Often manufacturers included an additional scale for peak AC voltage. There was no magic there; those scales were simply 1.414 times higher than the AC meter scale. If you need to calculate the peak voltage of true sinewave AC voltage, which is the peak voltage at the peak of the waveform crest, simply multiply the RMS reading by 1.414 to find the answer.

I’d bet many readers own a bench meter similar to the basic Heathkit model IM-13 vacuum tube voltmeter shown in Photo A. I built the kit in junior high school and it has served me well. It’s an averaging-type AC meter, with the inherent limitations mentioned above. It is also very representative of the sort of meter used in radio shops since the 1930s.
 

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SCANNING

Utility Communications Digest

Decoding MIL-STD-188-110A With MultiPSK In Test Stages

by John Kasupski, KC2HMZ

 

Users of the popular multimode digital communications program MultiPSK received some good news this August when the author, Patrick Lindecker, F6CTE, announced that he’s working on adding the ability to send and receive MIL-STD-188-110A, also known by its NATO designation STANAG 4539 and the civilian government designation FED-STD-1052, to the professional version of the program. Lindecker also released a test version of the program with the new function included.

MIL-STD-188 (Military Standard 188) is a series of telecommunications standards in use by U.S. military forces and government stations as well as those of several allied countries, and is also reportedly being used by the Chinese military. When first developed, MIL-STD-188 covered technical standards for tactical and long-haul communications, but subsequent revisions produced three series of subdivided documents, one of which is the current MIL-STD-188-100.
Lindecker also provided some insight on the structure of the waveform to the hobby radio community. “Each frame contains a synchronization preamble phase where the sub-mode is defined, a data phase where the unknown data is transmitted (mixed with known data to follow the transmission characteristics), an ‘End of Message’ phase, and a final flushing phase (to finish de-interleaving and de-convolution operations),” he told the Utility DXers Forum in announcing the test version of MultiPSK with the new “110A” function. “The software automatically decodes the speed (75, 150, 600, 1200, 2400, or 4800 bps) and the interleaver (short or long), in different character formats.”

Lindecker told Pop’Comm “at the moment it is just a test version. I’m beaconing 75 bps 110A just now.” He added that he hoped to have the “official” MultiPSK v4.15 ready in early September, with the 110A function included.

Now, of course, military and government stations do not produce MIL-STD-188-100 using software packages such as MultiPSK—they do so using radios that are designed to operate using the protocols specified by the standards, such as the Harris AN/PRC-152 (Photo A). For the curious—or those who just hate acronyms—the A and N stand for Army and Navy; PRC stands for Portable Radio Communications. However, such radios, as well as hardware-based packages sold for ham and hobby use, are priced well beyond the means of the average utility listener. The addition of MIL-STD-188-110A to MultiPSK makes this program an affordable and cost-effective alternative for digital decoding, especially since the program also already supports ALE decoding.

It’s important to note this since MultiPSK exists in two forms: a free version and a professional version. The capability to decode 110A will only be available in the professional version, currently priced at 30 Euros or $45.00 U.S. That’s still a lot less expensive than the available alternatives, especially with Skysweeper having been discontinued in June.

Upcoming NASA Launches

It’s been a while since we updated you on upcoming NASA mission launches. There’s one launch scheduled for this month and two for December. Those of you who enjoy listening to NASA comms during these launches will want to make a note of them.
 

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THE LIGHTER SIDE

Radio Fun

Trivia And Toons

by R.B. Sturtevant, AD7IL

 

Q. After World War II the Japanese took over most of the electronics manufacturing in the world. What were their wartime electronics like? Did this give them the springboard to take off in the field?

A. No it definitely didn’t. Their wartime electronics industry was way behind ours. The most advanced area of Japanese electronics was sonar, and it seems they got a lot of help from the Germans. They also never got around to putting the technology to the utmost advantage by developing attack capabilities using their sonar. They had no airborne radar in production at the end of the war, and their ground radar didn’t show up until 1942, even then it was a copy of German, British, and American designs. Their radio and radio direction finding equipment lagged behind as well.

Japanese training methods were also quite conventional and handicapped by the lack of technical background and electronics knowledge among the general populace. Later, faced with shorter training courses toward the end of the war, technical staff had to specialize in just one piece of equipment rather than several. Even their wire was judged substandard, probably a supply problem brought on by lack of supplies due to shipping problems.

How did the Japanese gain such a predominance after the war? They closely observed the American GIs and their electronics, learning everything they could. The man who would later head Sony Corporation was running a fix-it shop in Tokyo when a GI brought in a tape recorder for repair. The repairman had never seen one but took the job anyway. When he got inside he said “I can build one of these things”—and the rest is history.
 

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THE LIGHTER SIDE

The Loose Connection

Radio vs. Gardening: Bill Slam-dunks A Zucchini

by Bill Price, N3AVY

 

I’m sure there are people who look at radio amateurs and shortwave listeners and wonder what could possibly be the attraction. I know there are hobbies that leave me wondering the same thing. Probably the worst of all is gardening. How in the name of Hiram Percy Maxim could anyone enjoy doing the kind of work we typically hire illegal aliens to do for us because it’s a job that no American wants to do?

They may laugh at us for spinning a dial and listening to static and beeps and foreign languages and hams who talk like ducks, but it has to be better than driving to some place and spending money for a dozen clumps of dirt in plastic containers with some wisps of weed-like things sticking up from the dirt, then driving home and crawling in the dirt, digging and rearranging the mud and neatly arranging these little weeds in rows in the dirt, and pouring little bags of expensive dirt over them, then going into the house and washing up and watching television for a week until you can go out and notice that something has happened to your little weeds.

Imagine if we had to turn on our radios and tune a station then go and wait and watch television for a week to see if any sounds came out of the speaker!

Gardeners sometimes have it even worse! Sometimes they start with seeds! They dig and turn and churn and hoe and hum and loosen up all that mud, then stick some seeds into the ground, then go into the house and wash up and smear some foul-smelling menthol muscle rub all over their aching bodies and watch television for a week until they can go out and notice that some tiny green stem is sticking out of the ground where they planted their seeds. Zowie! What fun! These little green things don’t even send QSL cards!

I realize that we in the radio hobbies have sunspots, which sometimes limit our activity on some bands, and at some distances, but in general, there’s never been a time when we can’t find some interesting signals on some bands at any hour of the day or night.
 

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