The plane! The plane! (Part II)

Another great aspect of aviation monitoring takes place on shortwave radio. Over the open ocean, aircraft use HF frequencies to report their headings and altitudes to a worldwide network of shortwave-based control stations.

Worldwide HF aviation map.

Generally speaking, the traditional VHF air band and its line-of-sight characteristic is good to about 100 miles offshore, then HF radio, satellite navigation and the ACARS positioning systems take over. Fortunately for shortwave listeners, the North Atlantic and Caribbean air routes still use radio as a primary means of communicating.

From my listening post in New England, the North Atlantic air route is the busiest and easiest to monitor. There are seven North Atlantic "tracks" (NATs) that accommodate flights between the U.S. and Europe - most of which are eastbound by night and westbound by day. Gander Oceanic Control (Gander Radio) in Newfoundland controls the western side, while Shanwick Control in Ireland keeps tabs on the European side.

Shortwave frequencies for the North Atlantic tracks are 2899 kHz, 5616 kHz, 8864 kHz, 13291 kHz and 17946 kHz. All transmissions are in USB and frequencies vary by time of day and propagation.

Photo courtesy of Flightaware.com

Aircraft crossing the oceans must report in as they cross various points of longitude (called "waypoints") along each track, allowing controllers to maintain safe separation between planes. The ground controllers also receive SELCAL (selective calling) codes from the crew that allows the cockpit to be notified of incoming transmissions while leaving the radios muted.

Controllers also test the tones to make sure the radios activate properly. The website Code7700.com explains the history of SELCAL, which has been around for 60 years and adapted to the increasing amount of air traffic over the years.

Another important oceanic station is New York Radio, located in Ronkonkoma, New York, in the same building as New York Center, the regional VHF control facility. New York Radio controls a huge swatch of air space including the Gulf of Mexico, most of the Caribbean, parts of the NAT (zones 6 and 7) and part of the South Atlantic Tracks (SATs).

New York Radio's overseas "opposite" is Santa Maria Oceanic in Portugal, sharing these HF frequencies: 2962 kHz, 6628 kHz, 8825 kHz, 11309 kHz and 17946 kHz.

Much of the aviation electronics (avionics) for both military and civilian aircraft communications is manufactured by Rockwell-Collins of Cedar Rapids, Iowa. The company's line up of integrated HF radio and digital data equipment can be found here.

Finally, please enjoy this beautiful animation, depicting the thousands of flights that cross the Atlantic Ocean each day. Video is courtesy of Aerosavvy.com and Vimeo,com.

The plane! The plane!

From where I live in southwestern Connecticut, it seems that air traffic is everywhere.  Small planes loop about from uncontrolled (no tower) airports, commuter planes buzz overhead from larger controlled facilities, and  jumbo jets fly a regular path from southwest to northeast, heading to various destinations in Europe.

As a radio hobbyist, it's really easy to listen, since planes still use VHF AM to talk with controllers, just as they have since world War II.  The American air traffic control system - complex and laden with acronyms and jargon - is divided into 22 large sectors which direct planes before and after they talk to local airports.

Sector map for Boston ARTCC

The New England states, plus part of New York and eastern Pennsylvania, are part of the Boston Air Route Traffic Control Center (Boston Center) based in Nashua, New Hampshire. Since Boston Center covers so much territory - 165,000 square miles - it has remote radio sites all over the northeast, on Cape Cod and in two Connecticut towns, Shelton and Woodstock. View a complete list of frequencies here.

The busiest of these frequencies by far is 118.425 MHz, a high-altitude channel for flights entering and leaving Boston Center's western sector. It is so busy that 10 seconds rarely elapse without another plane signing on for altitude ("flight level") and radio frequency changes - depending on where they are headed.

Waterbury-Oxford (CT) Airport

Among major airports under Boston Center's control, I can hear Bradley International Airport tower on 120.3 MHz and Bradley approach and departure on 123.95 MHz. The largest of the New England airports, Logan Airport in Boston, (tower on 128.800) is too far away for me to hear directly - but it can be monitored through the online aviation service LiveATC.net.

I also have small controlled airports nearby, business-based Tweed-New Haven with a tower frequency of 124.8 MHz, unicom of 121.700, and Waterbury-Oxford Airport tower on 118.475 MHz, unicom of 122.95. The towers at these airports shut down at 10 p.m., so the unicom channels are used by aircraft to announce their intentions (landing, taking off, taxiing) during nighttime hours.

Closest to me at about 10 miles away is Meriden-Markham Airport, somewhat of a glorified airstrip. The airport has no tower and is popular with flight instructors and students. Its unicom frequency is 123.050 and, like the others, is busiest on weekends.

Unicom channels can provide hours of entertainment, as pilots chit-chat about their lives, loves and just about anything else. This is common on clear summer and autumn days, when hobby pilots take to the skies for sightseeing or a day trip to Martha's Vineyard or Nantucket. Try tuning to 123.07 122.700, 122.800, 122.900, 123.000 or 123.050, or a few other known "itinerant" aviation channels where anything goes: 123.300, 123.500, 123.025 (helicopter) and 122.750 (fixed wing). Supposedly 123.45 is the unofficial plane-to-plane frequency, but I almost never catch any chatter there.

Screen capture of air traffic over
Connecticut from Flightaware.net

Here's a fun fact - VHF radio can be heard over incredibly wide areas, based on this formula: Distance (miles) = 1.23 x (the square root of) altitude (feet). This means that an aircraft at 10,000 feet can be heard at a distance of 110.9 miles - which is slightly less than the distance from my house to Boston.

If listening isn't enough for you, there are websites that offer aircraft tracking in real time, complete with flight plans and information about the planes, with the simple click of a mouse. Of three similar sites, my favorite is www.adsbexchange.com because it plots both civilian and military aircraft based on commonly used ADS-B transponders and MLAT - a radar triangulation system for planes without ADS-B.

The other online flight trackers are Flightradar24.com and Flightaware.com, the second of which distributes self-contained ADS-B receivers to users who live where there is sparse transponder reception, provided the user streams the data back to the main site.

Aircraft also communicate over the open ocean, but at that distance, HF radio replaces VHF and Oceanic ATC stations handle all the communications. More on that in my next blog entry!

Field Day! Field Day!

After 34 years in ham radio, I still look forward to Field Day, the contest and social event where radio voices mingle with the sound of generators, camaraderie and (if you're lucky) the wafting scent of burgers and hot dogs on the grill.

The concept is simple: ham operators - working mostly off the grid - compete with other operators in the U.S and Canada to rack up contacts, sharpen their skills and show the public what amateur radio is all about. Most stations use generators or batteries, some stay on commercial power, while a brave few try something more exotic, like solar or wind power.

W1AMJ at Waterbury (CT) Amateur
Radio Club Field Day.

Field Day is sponsored by the American Radio Relay League, the prime mover and shaker in the ham radio hobby. The ARRL maintains a Field Day registry website, and 1200 ham groups have already signed on for this year's competition, the weekend of June 24-25. Use the above link find a site near you, then stop by for a firsthand look at ham radio in progress.

At the risk of sounding like a curmudgeon, I think Field Day - and ham radio in general - doesn’t hold the mystique and prestige that it once did. My recollections go back a long way, because my dad was a ham operator in the '50s and '60s – in fact, he was (as far as I know) the original W1AMJ. 

On the last weekend in June, he and his ham friends would haul their radios and antennas to Bethlehem, Connecticut and set up operations as part of the Hen House Gang ham radio Field Day. I never went with them, but looking back, I really wish I had for the sake of nostalgia. I remember that my dad was missing for a day or two, and my mother said he was “with the ham radio guys” for the weekend.

Les, KB1SL at Waterbury
Amateur Radio Club Field Day.

Ham radio was really a measure of technical skill and prowess in the ‘50s and ‘60s. Radios were big, bulky, tube-driven and drifty and hams repaired their own equipment, even at the risk of a high voltage zap. It was a challenge and a privilege to become a ham operator, and hams were usually the communications arm of local and state civil defense. There were no FEMA courses, CERT teams or ARES groups, which were still several decades away.

Then the '70s and ‘80s happened. Ham radio was miniaturized – on its way to being micronized - and operators no longer had to change tubes, solder components or build anything - unless they wanted to. The whiz-bang factor still existed because it was possible to talk to the other side of the world without using a telephone, and to make phone calls from a car using the autopatch feature on two meter repeaters.

A Yaesu FT-950 at W1LAS, the
club station of the WARC.

The Internet was born and raised in the 1990s, and the excitement of ham radio declined a lot in the public eye. Now, in 2017, it’s very hard to pitch the radio hobby to young people, or for that matter, to anyone with a computer and the power of digital communication at their fingertips. The whiz-bang factor has left the building.

Still and all, amateur radio survives and even thrives on some levels. The entry-point Technician license is very popular, and one reason for that is ARES, the Amateur Radio Emergency Service, which has attracted people interested in emergency communications in their home towns. Many Technicians never venture outside of FM repeaters, so Field Day offers the chance to try the HF bands, compete with static, fading, noise and interference - my kind of radio!

Desperately seeking digital

My radio hobby occasionally takes me out of the mainstream and into the esoteric. As an example, I chase HD broadcasts on AM, especially ones that aren't local and pose a challenge to pick up and decode. Essentially, it puts a new spin on the old hobby of AM radio dxing.

When (and if) you hear about HD radio, you probably first think of FM and the variety of programming on the secondary channels (HD2, HD3 and even HD4, where HD1 is the digital version of the main format.) Despite rumors of its demise, HD is still alive on the AM band, where the digital effect is really impressive. On AM, HD sounds like FM  mono - no static at all (apologies to Steely Dan), accomplished by buffering a slow data stream into full fidelity flawless audio.

HD on AM hasn't gotten much positive press in the 15 years it has been around - in fact, it has been maligned because of interference to adjacent channel stations, especially at night.  As a result, many stations that jumped on the bandwagon early are now turning HD off at night, or have dumped it altogether.

Generally, larger corporate-owned AM stations are still in the HD game, especially those owned by iHeart and CBS, which may have a financial stake in the success of digital radio, Smaller stations, the mom-and-pop shops that are struggling anyway, can't justify the expense of licensing fees, new transmitters and improved antenna systems for what amounts to minimal returns on the investment.

A complete list of AM stations licensed for HD can be found on this FCC page.

Unfortunately, conventional radios can't receive HD, but they are available on the retail market. Also, many high end new cars include HD as a standard feature, and portable and tabletop radios can be ordered online or found at electronic retailers like Best Buy and Crutchfield. Many of the available units are FM only, but a few also include AM, which generally plays second fiddle to FM in the analog world.

Listening during the day at home, I can decode broadcasts from Connecticut stations WTIC and WELI and New York powerhouses WCBS and WINS. Nighttime brings WBZ in Boston and occasionally others, like WHAM in Rochester, New York. One of these evenings, I hope to decode WGY at 810 kHz, where I pick up a blinking HD icon and strong signal, but no digital lock.

I was lucky enough to find a Sony XDR S10H tabletop receiver before it went out of production a few years ago. The unit has separate FM and AM antenna connectors, and the AM side is currently hooked up to my homemade AM rotatable loop.

American hams get two new bands!

Ham radio has been on the FCC radar lately, with the creation of two new bands at the lower end of the HF spectrum -  one just below standard AM radio, and the other way below that - on longwave frequencies.

The bands were announced in the FCC's latest Report & Order last month - particularly good news for the ARRL, which has pressed for a band in the 500 kHz range since the 1990s, when the maritime industry vacated HF in favor of global satellites.

Here's what will be gained for U.S. hams:

• Frequencies between 472-479 kHz (630 meters) with a maximum power of five watts (except in parts of Alaska within 500 miles of Russia, where the maximum will be one watt.) All narrow modes will be allowed, but slow-speed CW (QRSS) and software digital modes will be the most common. 

Ham radio is considered a secondary usage and must not interfere with  power line carrier systems (PLCs), used to manage the electric grid.  The website 472khz.org is a great primer on the equipment, modes and antennas needed for this new band, which comes years after the FCC began issuing experimental licenses for operation just below 500 kHz in the WD2XSH program.

• Frequencies between 135.7-137.8 kHz (2200 meters) with a maximum power of one watt. This band really isn't for the fainthearted or the non-technical, in light of the enormous wavelength (more than a mile for a full wave), the need for precise circuit-tuned and radial-grounded antennas, and mostly kit-assembly transmitters. 

At 136 kHz, static is a real killer, and signals are best seen with computer software rather than heard through a speaker. Still and all, hobbyists (called "lowfers") have been experimenting on longwave for many years - around 160 kHz - with very low power beacons and impressive transcontinental results.


The FCC still hasn't issued a start date for these new frequencies, but ARRL CEO Tom Gallagher couldn't be happier. “We are excited by the FCC’s action to authorize amateur radio access for the first time on the MF and LF spectrum," he said.
"As amateurs begin using these new allocations in the next few weeks, we encourage the entire Amateur Radio community, as secondary users, to be especially attentive to the rules.”

Personally, I won't be transmitting on either of these new bands due to their demanding antenna requirements, but I am waiting for the FCC's final ruling on 60 meters, which might expand the present arrangement of a four fixed 5 MHz frequencies, to a frequency range similar to what other countries have.

Radio Garden is worth a visit

As I may have mentioned previously, radio and the internet make a great team. One enhances the other, like Burns and Allen or Burns and Schreiber. (Remember the '70s?) For music and information fans, there are more options than ever - streamed right to your computer from anywhere on the planet.

Streaming audio is two decades old now, so the cool stuff is in the presentation.  Such is the case with Radio Garden, an interactive website that's possibly the most addictive thing I've encountered online. I return to it again and again, like a kitten drawn to a shiny object.

Radio Garden screen capture

Radio Garden is the creation of the Netherlands Institute for Sound and Vision as part of its "Transnational Radio Knowledge Platform,"  a study of radio's impact on making the world a smaller, friendlier place.

The interface for Radio Garden resembles Google Earth, and users can turn the globe with the swipe of a mouse. As Earth rotates, luminous green dots representing radio stations appear on almost every continent - more than 8,000 in all, and the number is growing. Simply click on any dot to bring in one or several stations from that area.

Jonathan Puckey, a Danish designer who came up with the rotating sphere concept, recently told NPR that the site went viral almost immediately and there are constant requests from radio stations who want to be added to the collection.

There are four Radio Garden modes: live radio; a history section with vintage audio clips; jingles from all over the world; and listener stories about the transcendental nature of radio, versus political and geographic boundaries.

It's all there. Every conceivable radio format - the mundane and the exotic, commercial, non-commercial, special interest, religious, and micro broadcasting.There are even some scanner feeds included on a few of the American green dot locations. (As I write this, I'm listening to  "Geronimo 106.1 FM" from Dangdut, Indonesia, which features American-style pop and a hip-hop music.)

So find the site, spin the globe and click on a dot. You'll find the world really is a smaller place sometimes.

HamSphere - a simulation worth checking out

Some things really aren't worth getting upset over, but it never fails to surprise me what ham radio operators will get their knickers in a twist about. Before I make my main point, let me set up an analogy:

Pilots fly real airplanes and also use computer simulators, either to hone their skills or just for fun. Non-pilots obviously also use simulators, and no one from the aviation community tells them to quit and go to flight school if they're that interested in airplanes. But in the sometimes judgmental world of amateur radio, there are operators upset over a simulation called HamSphere, an online program that looks and behaves just like shortwave radio.

HamSphere 3.0 transceiver.

"Let 'em get a ham license if they're interested in radio," goes the argument. "It's nothing but a chat room with sound effects," the naysayers claim. (This is where I picture ventriloquist Jeff Dunham's cranky sidekick, Walter, venting an opinion.) As a licensed ham and a HamSphere user, I disagree. HamSphere 4.0, the most recent version, takes into account everything about HF - static, fading, interference, day-night propagation, even antenna gain - courtesy of complex algorithms developed by Kelly Lindman (5B4AIT), a radio operator from Cyprus, who has made this project his life's work.

HamSphere does not claim to be real ham radio, and Lindman wants to make that clear.

Currently there are two desktop HamSphere versions available. Version 3.0 is a basic nine-band transceiver with a host of features - a spectral display, an analog S/RF meter, and a big VFO knob for fast tuning. This is now considered a starter radio in preparation for the "flagship" 4.0 version - a modular, endlessly scalable radio that accepts plug-ins for antennas, rotors, filters, sound equalizers and even a real-time gray line world map.

HamSphere 4.0 transceiver.

HamSphere isn't free. A one year membership costs 30 Euro, or about $34, but items in the HamSphere store (yagi antennas, filters, audio playback recorders and rotors) are purchased a la cart, and if you're an impulsive person (like me) this can really add up.

The simulation is open to licensed hams who can use their actual call signs, and to unlicensed users, who are assigned unique HamSphere call letters. Lindman has set up HamSphere DX contests, a spotting network, an awards program, online QSL cards for members and a quarterly newsletter. Yes, there is such a thing as rare dx on HamSphere, and operators spend as much time chasing it as their real world counterparts do.

I operate all three versions of HamSphere, including the iOS mobile version. They are all simple to download and operate, but it takes some tweaking of the audio input to get decent sounding "transmit" audio from the computer sound card to avoid distortion. Versions 3.0 and 4.0 don't interact with each other, and there still seems to be a lot less activity on 4.0, but it might have to do with the time that I log in, generally during the evenings, EST in the United States.

A sampling of HamSphere awards.

In closing, let me say HamSphere is a lot of fun. Maybe it's a training ground for potential hams, or maybe it isn't. Other users have told me that it's the closest they can get to amateur radio for any number of reasons; antenna restrictions, health problems and apartment dwelling among them.

There are over 16.000 registered users in 200 countries, and HamSphere has a very active Facebook group.