Author Archive

Saving Your Amateur Radio Club, the Airspy HF+ Discovery, and More

Stories you’ll find in our September, 2019 issue:

TSM Reviews:
Airspy HF+ Discovery: It’s a Whole New World of Radio
By Larry Van Horn N5FPW and Gayle Van Horn W4GVH

While the term “digital radio” has been around since the 1970s in US government circles, it wasn’t until 1984 that the term “software defined radio” first surfaced. At first, many old-timers in the radio hobby scoffed at the idea that any radio that didn’t have a tuning knob and all the circuitry associated with it was a real radio. People pushing a computer-based technology were on the outside looking in as far as major manufacturers were concerned. It did not take long for software defined radio, or SDR, to come out of the shadows and be embraced by the radio hobby industry. Larry takes a look at the Airspy HF+ Discovery, the latest in a series of high-performance, low cost SDRs that are changing the world of HF radio listening.

Digital TV Ten Years Later and ATSC 3.0 Today
By Ken Reitz KS4ZR

The mass migration of analog television transmissions to digital television (DTV) broadcasting in the US officially went into effect June 12, 2009. The run up to the switch was years in development and involved extensive technical testing and a huge investment on the part of broadcast TV interests. There was nothing smooth about the transition. Ten years later, the dream of HDTV with 5.1 Dolby Surround Sound has faded considerably, with few channels actually achieving that benchmark. Now the FCC is preparing to do it again—this time with DTV’s successor: ATSC 3.0, which promises landmark 4K Over-the-Air TV channels and auxiliary channels in HDTV. Unfortunately, ATSC 3.0 is not compatible with any ATSC 1.0 TV sets in use today. Having failed to deliver ATSC 1.0, will the broadcast TV industry be able to deliver on ATSC 3.0.? And, anyway, whatever happened to ATSC 2.0?

The Hunt for the Bismarck
By Scott A. Caldwell

Summer 1941 was a dark time for the British Empire, which in reality was alone and isolated. Nazi Germany was rampant in its military conquest of mainland Europe and now one of the most powerful battleships in the world was ready for a commerce raiding campaign in the North Atlantic Ocean. The pursuit and sinking of the Bismarck was a turning point in naval strategy that was based on the utilization of a central command structure, which acted as a clearing house for intelligence information. Scott examines the communications systems used by both German and British commanders and how mistakes were made on both sides that led to the sinking of both German and British naval vessels and how the eventual sinking of the Bismarck became a turning point in the war for sea superiority.

Zen and the Art of
Amateur Radio Club Maintenance – Part 2
By Cory GB Sickles WA3UVV

If you did your homework from the previous installment, you have some better perspective into the size, finances, direction and overall health of your amateur radio club. Hopefully, you did not find yourself in or on the edge of critical mass, where your organization is about to fail. Even if you did, there is probably time to still be able to turn things around. If not, then perhaps the answer is to reflect on what went wrong and start anew. Cory gives us all more tips on how to save your ham club from itself.

Scanning America
By Dan Veeneman
Scanning Sumner County, Tennessee

Federal Wavelengths
By Chris Parris
Nevada DoE Update; FAA Closeup

Milcom
Larry Van Horn N5FPW
Phantoms in the Desert

Utility Planet
By Hugh Stegman
It’s Summer “Numbers” Time!

Shortwave Utility Logs
By Hugh Stegman and Mike Chace-Ortiz

VHF and Above
By Joe Lynch N6CL
PTRX-7300: A Panadapter Module for the IC-7300

Digitally Speaking
By Cory GB Sickles WA3UVV
Digital Voice Moves On

Radio 101
By Ken Reitz KS4ZR
Hits and Misses: Grace Digital Mondo+

The World of Shortwave Listening
By Jeff White, Secretary-Treasurer NASB
Can the Internet Replace Shortwave? Plus: NASB and SWL Fest 2019 Report

The Shortwave Listener
By Fred Waterer
WWII Radio Commemorations

Amateur Radio Satellites
By Keith Baker KB1SF/VA3KSF
Amateur Radio Satellite Primer (Part V)

The Longwave Zone
By Kevin O’Hern Carey N2AFX
Gearing Up!

Adventures in Radio Restoration
By Rich Post KB8TAD
Reviving a “Poor Man’s Collins” The Heathkit SB-301 Receiver

Antenna Connections
By Dan Farber AC0LW
Top Band: Antennas for 160 Meters

The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.

Yagis, DMR Portables and Underwater Communications

Stories you’ll find in our August, 2019 edition:

The Yagi-Uda Mystery: The Remarkable Backstory of this Ubiquitous Antenna
By Richard Fisher KI6SN

Shintaro Uda and Hidetsugu Yagi were mirror images of the antenna they created in 1926—known around the world today simply as the Yagi—an array invented by Uda in collaboration with Yagi. Ninety-three years later, this design is still widely in use for both amateur and commercial installations on the HF, VHF/UHF bands and beyond. It is the antenna so often seen atop amateur radio towers, at military installations and many municipal and commercial buildings. Yet Shintaro Uda seems to have faded from the picture of the origins of this antenna. Richard tells us about two stories of intrigue and historical significance behind the Yagi.

TSM Reviews: Yaesu FT3DR and Radioditty GD-73A
By Cory GB Sickles WA3UVV

The Yaesu FT3DR and the Radioddity GD-73A are two very different digital voice (DV) portables, with widely divergent feature sets. Each needs to be considered for its merits and the applications you have in mind. The Yaesu FT3DR is the latest of a series of DV hand-held portables with the features you’d expect from a full-featured HT. The Radioddity GD-73A is a UHF-only, DMR/analog portable with minimal features: There is no provision for an external antenna and the internal one protrudes under plastic, much in the same way as a 0.5-watt blister-pack FRS (Family Radio Service) transceiver is packaged. Cory goes deep into the details and tells us there’s more to each than may be at first apparent.

The USS Thresher on Eternal Patrol
By Scott A. Caldwell

The USS Thresher(SSN 593) was an icon of the United States Navy and was often used in recruitment posters. She was regarded as the most technologically advanced submarine in active service, designed to hunt and engage Soviet submarines that patrolled the deep North Atlantic Ocean. Her loss on April 10, 1963 shocked the entire nation and the subsequent inquiry raised more questions than answers, in light of the confusing radio transmission with the submarine escort vessel USS Skylark (ASR 20). Underwater communications were subjected to temperature and density fluctuations that often deflected and distorted the amplitude of the sound waves. Scott looks at the difficulties of undersea communications while telling the story of this disaster.

The Care and Feeding of Electronic Equipment: Part 2
By Robert Gulley K4KPM

Electronic equipment for our radio hobby requires periodic checks for proper operation, as well as occasionally performing preventive maintenance or repair as needed. This includes radios, power supplies/connections, computer hardware, antenna systems, and a host of other potential troublemakers. In this second article Robert discuss troubleshooting tips, electrical and antenna system maintenance, computer hardware/software updates, and other preventative measures to help keep things running as smoothly as possible.

Scanning America
By Dan Veeneman
Scanning Michigan

Federal Wavelengths
By Chris Parris
Las Vegas Mysteries and Frequencies

Milcom
By Larry Van Horn N5FPW
A New Way to Monitor the Military on January 1, 2020

Utility Planet
By Hugh Stegman
Cycle 25: Coming to an Ionosphere Near You

Shortwave Utility Logs
By Mike Chace-Ortiz and Hugh Stegman

VHF and Above
By Joe Lynch N6CL
The ‘Ah-Ha’ Behind Some Types of Aurorae

Digitally Speaking
By Cory GB Sickles WA3UVV
Another Look at D-Star

Radio 101
By Ken Reitz KS4ZR
The Trouble with Alexa

Radio Propagation
By Tomas Hood NW7US
Sunspot Cycle 24 Solar Minimum is Coming!

The World of Shortwave Listening
By Rob Wagner VK3BVW
Whatever Happened to the 11-Meter Band?

The Shortwave Listener
By Fred Waterer
German via Shortwave Plus BBC Highlights

Amateur Radio Astronomy
By Stan Nelson KB5VL
The Next Generation Very Large Array: ngVLAA

Adventures in Radio Restoration
By Rich Post KB8TAD
The Rolls-Royce of Radios: National HRO Part 2

Antenna Connections
By Dan Farber AC0LW
The End-Fed Antenna

The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.

Superpower AM Radio, Vacuum Tube Voltmeters, Picosatellites and Antennas for 6 Meters

Stories you’ll find in our July, 2019 issue:

Superpower AM Radio in the United States: Why it Failed
By John F. Schneider W9FGH

The term “superpower” was used frequently in the early years of American radio broadcasting, but its exact definition was continually evolving. In 1923, superpower referred to the newly-authorized 1,000 watt “Class B” stations. By 1926 WGY, Schenectady, New York, conducted the first ever test at 50,000 watts. By 1930 WGY had conducted tests at 200 kW, a signal heard in Alaska and Hawaii. But that station was not alone. Many others were eager to explore the possibilities of even higher power: 500 kW! What happened to all that enthusiasm for superpower? John goes deep into this engineering and regulatory jungle that saw broadcast titans trying to use the FCC to dominate America’s airwaves.

Rocking the Stasi
By Scott A. Caldwell

In June 1961, Berlin was a divided city. Viewed from the outside, East Germany, which surrounded Berlin, represented a closed society, dominated by the secret police known universally as the Stasi. But East Germany was vulnerable to Western culture and political ideology through the medium of radio that could not be regulated by the Stasi or the ruling Socialist Unity Party, which resulted in an electronic war of the ether. Scott traces the course of this battle of the airwaves that lasted from the end of World War II to the 1980s and the end of the Cold War.

Overlooked Radio Heroine: The Life, Work and Inventions of Hedy Lamarr
By Georg Wiessala

Hedy Lamarr was born in Austria in 1914 and rose to stellar fame in Hollywood as a film actress and as a multi-talented inventor. Georg looks at the life and work as his most favorite (and most overlooked) radio heroines, without whom today’s Wi-Fi, GPS and Bluetooth technologies would be impossible. He explains why The Guardian claimed, “Lamarr’s story is one of a brilliant woman who was consistently underestimated.”

Inside the VTVM: Lafayette KT-174 and PACO V-70
By Rich Post KB8TAD

The VTVM (vacuum tube voltmeter) was the standard instrument for measuring DC and AC for radio and television service shops from the late 1940s to the end of the vacuum tube era in the 1970s. The sensitivity of the typical service VTVM on DC measurement was 11 megohms regardless of scale. Specialty VTVMs such as the Hewlett-Packard HP-410 offered much higher sensitivity but were high-priced lab-quality instruments and not typically found in radio-TV service shops. Rich takes a close look at two amateur favorites from the era.

Scanning America
By Dan Veeneman
Oakland County (MI); Jasper County (MO)

Federal Wavelengths
By Chris Parris
NIH Trunked System Update

Milcom
By Larry Van Horn N5FPW
Monitoring Air Route Traffic Control Centers

Utility Planet
By Hugh Stegman
Chasing German Weather RTTY

Shortwave Utility Logs
By Hugh Stegman and Mike Chace-Ortiz

VHF and Above
By Joe Lynch N6CL
Opensource Picosatellite Development

Digitally Speaking
By Cory Sickles WA3UVV
The Network is the Repeater

Amateur Radio Insights
By Kirk Kleinschmidt NT0Z
100 Years from Now

Radio 101
By Ken Reitz KS4ZR
Emergency Preparations

Radio Propagation
By Tomas Hood NW7US
Current Rough Shortwave Conditions

The World of Shortwave Listening
By Ken Reitz KS4ZR
Digital Radio Mondiale: Testing, Testing, Testing

The Shortwave Listener
By Fred Waterer
World Sport Coverage on Shortwave; July Shortwave Programming Update

Maritime Monitoring
By Ron Walsh VE3GO
Water, Water, Everywhere!

Adventures in Radio Restoration
By Rich Post KB8TAD
Introducing the National HRO

Antenna Connections
By Dan Farber AC0LW
Magic Band: Antennas for Six Meters

The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.

Digipeating the ISS, RTTY and QRP

Stories you’ll find in our May, 2019 issue:

Digipeating: APRS to the International Space Station – At Your Convenience
By Richard Fisher KI6SN

Making contact with the International Space Station by amateur radio is challenging on its face—the ISS orbit must be somewhere above your horizon; it is a moving target, and your antenna needs to be tracking its position as the space station moves across the sky. For FM voice contact, you may be in competition with lots of other Earth-based stations with the same goal as yours. But, thanks to the ISS’s digital repeater, contact with ISS is quite possible, but even so, for success, there are still lots of stars that must align. Richard tells us how it’s done.

TSM Reviews: The Mobile VHF/UHF COMPACtenna
By Bob Grove W8JHD

Is it possible for a 7.5-inch antenna to provide equal, or even superior, performance compared to a conventional 18-inch whip? After all, doesn’t a longer element capture more signal energy than a smaller element? Even with some reduction in signal strength, would overall improvement in uninterrupted reception translate to better performance? Bob examines this new mobile VHF/UHF antenna.

TSM Reviews: COMPACtenna for Shortwave
By Chris Parris

Chris was recently offered a chance to use the COMPACtenna SW (shortwave) model at home. The “SW” specifications show that it is 20 inches tall, designed for continuous receive over 3 MHz to 30 MHz and uses a standard 3/8-inch – 24 thread mount that most CB antennas are designed for. As someone who has tried for many years to find a good mobile/portable shortwave antenna solution, this seemed too good to be true. He decided to take the COMPACtenna out and try it on his personal vehicle along with several radios and other shortwave antennas to see how it fared.

RTTY: Old School Digital
By Cory GB Sickles WA3UVV

In his previous articles about other forms of digital communications as well as his three-part series on “Piggy Bank Ham Radio,” Cory found that there appears to be a good deal of interest in radioteletype and a desire to use some older gear. Coupling that with questions about pre-1990 HF rigs, there would seem to be a convergence of ideas. While older gear may not be suitable for the latest in digital modes, they are still perfectly fine radios and the fun of RTTY awaits you – with several ways to get on the air. Cory traces the history and continued use of this vintage amateur mode.

CRKits HT-1A Dual Band QRP Transceiver
By James Hannibal KH2SR

This dual band transceiver, available as a kit or factory-built, has a transmit frequency range of 7.0-7.2 MHz and 14.0-14.35 MHz. And, even though it only transmits CW, it does have the ability to listen to SSB signals. It also has an extended receive range, covering everything between 5.9-16 MHz, which means shortwave broadcast reception while in SSB mode. James puts this little rig to the test as it was meant to be used, outside in the wild with a small battery pack and portable antenna.

Scanning America
By Dan Veeneman
Groton, Connecticut; Amtrak Update

Federal Wavelengths
By Chris Parris
Have Scanner, Will Travel

Milcom
By Larry Van Horn N5FPW
Monitoring the 14thFighter Training Wing

Utility Planet
By Hugh Stegman
South Korean HFDL Takes Off

VHF and Above
By Joe Lynch N6CL
Owen Garriott W5LFL Silent Key

Digitally Speaking
By Cory GB Sickles WA3UVV
Get Yourself Connected

Amateur Radio Insights
By Kirk Kleinschmidt NT0Z
Are You a Member of the “Tower Tribe?”

Radio 101
By Ken Reitz KS4ZR
Baseball on the Radio: 2019

Radio Propagation
By Tomas Hood NW7US
E-Layer Sporadic Ionospheric Propagation

The World of Shortwave Listening
By Jeff White, Chairman, HFCC
Shortwave Broadcasters Discuss Future of the Medium and Time Changes or Does it?

The Shortwave Listener
By Fred Waterer
Radio Lectures; Classical on SW and Radio Santa Cruz

Amateur Radio Astronomy
By Stan Nelson KB5VL
Long Duration Meteor Trails

Adventures in Radio Restoration
By Rich Post KB8TAD
Millen’s Ham Superhet: The National FB-7

The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.

Ham-flavored STEM, the ISS Calling CQ, and Grounding

Stories you’ll find in our April, 2019 edition:

TSM Reviews: Uniden SDS100 Base/mobile Scanner
By Larry Van Horn N5FPW

On the heels of the release of the SDS100 handheld scanner in the first quarter of 2018, Uniden announced the release of the SDS200 base/mobile scanner in January 2019. Like the SDS100, the SDS200 is a True I/Q™ scanner, that incorporates software defined radio technology to provide improved digital performance in even the most challenging RF environments.

What sets the SDS100/200 series scanners apart from any others in the marketplace is their ability to handle simulcast reception issues while monitoring certain P25 trunk radio systems. Larry takes a look at this talented scanner in part two of “The Good, the Bad and the Ugly.”

Bringing Ham Flavored STEM into the Classroom
By Martha Muir W4MSA

Members of the North Fulton Amateur Radio League (NFARL) spent a week working with some seventh and eighth grade students at Mill Springs Academy in Alpharetta, Georgia, teaching them some fundamental concepts of electronics with direct applications related to amateur radio. This is part of a program at Mill Springs called Winter Learning, where students get to take a weeklong seminar on a specialty topic. This specialty topic, “Electricity is Magnetic!” was organized by NFARL members, Chuck Catledge AE4CW and Jim Stafford W4QO. Martha tells us what happens when Science Technology Engineering and Mathematics meets amateur radio in the classroom.

Portable Airband Transceiver Overview
By Cory GB Sickles WA3UVV

The VHF spectrum is full of FM analog and various forms of digital voice and data communications, but also found there are communications based on a technology that goes back a century and then some—AM or Amplitude Modulation. This is the type of signaling shared by commercial and general aviation pilots, as well as the men and women on the ground that communicate with them to keep everyone safe and moving efficiently. If you live near an airport of any size you may have wondered about listening in. Cory takes a look at listening to this small but important slice of the spectrum.

Othernet’s Free Satellite Service Continues to Evolve
By Kenneth Barbi

The free one-way digital satellite service, known as Othernet, has been evolving since its debut in 2017. Othernet had operated first on Ku-band and then on L-band, and though coverage was worldwide, the cost was astronomical, and the throughput was limited to 20 MB per day. By reconfiguring their operation back to Ku-band, costs came down and throughput increased to more than 1 GB per day. But the change required different hardware. Kenneth updates the latest on this non-profit information service.

Scanning America
Dan Veeneman
TETRA System; FCC Actions; Clark County, Ohio

Federal Wavelengths
By Chris Parris
Federal Radios Fading Away?

Milcom Monitoring
By Larry Van Horn N5FPW
Monitoring the Pakistan-India Navies

Utility Planet
By Hugh Stegman
North Korean “Numbers” Messages Continue

Shortwave Utility Logs
By Mike Chace-Ortiz and Hugh Stegman

VHF and Above
By Joe Lynch N6CL
ISS Astronauts are Calling CQ Students

Digitally Speaking
By Cory GB Sickles WA3UVV
Split P Soup

Amateur Radio Insights
By Kirk Kleinschmidt NT0Z
Down to the Wire

Radio 101
By Ken Reitz KS4ZR
ATSC3, 4K and 5G: What Next?

Radio Propagation
By Tomas Hood NW7US
A New Cycle is Born

The World of Shortwave Listening
By Rob Wagner VK3BVW
Hunting Shortwave Schedule Changes

The Shortwave Listener
By Fred Waterer
Slovakia on Shortwave, RNZI, Plus BBC Programming this Month

Maritime Monitoring
By Ron Walsh VE3GO
Winter Winds, Spring Melt and Radio

Adventures in Radio Restoration
By Rich Post KB8TAD
Still a Thrill: The National SW3 “Thrill Box”

Antenna Connections
By Dan Farber AC0LW
Well Grounded: A Down to Earth Station

The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.

SDR, ham radio satellites, and antennas over amplifiers

Stories you’ll find in our July, 2018 issue:

TSM Guide to Monitoring Air Shows
By Larry Van Horn N5FPW

Every year from March through November, millions of people hit the road to watch the excitement and thrills as military and civilian aero teams put their high-performance aircraft through their paces to entertain the crowds and perform at air shows all over the world.But you can add to the experience by monitoring the performing teams’ radio communications. With a radio scanner in hand, you will experience a whole new perspective of the show that few attendees will experience. Larry lets us all in on the frequencies used by all participants in these shows in VHF and UHF civilian and military bands.

A Look Back at the 2018 Air Shows
By Brian and Jo Marie Topolski

Air shows offer a variety of aerial action and every year is a little bit different. Veteran air show attendees, Brian and Jo Marie, give us a look ahead at the 2019 season and a look back at what happened last year. Among the new teams to look for this year are the Royal Air Force aerobatic jet team known as the Red Arrows and the US Department of Defense F-35A Lightning II demonstration team. Brian and Jo Marie tell you where you are likely to hear communications from these teams as well as all of the others. The duo also takes a look back at the losses that occurred during last year’s air show season.

Photos from 2018:
B-52 Stratofortress; Japanese Navy Type 97; Mitchell B-25
By Brian and Jo Marie Topolski

It’s hard not to be attracted to the impressive sight of a Blue Angels or Thunderbirds aerial demonstration. The number of planes in the air at once, the deafening sound of their pass across air show center are thrilling. But there are plenty of quality side shows as well. Brian looks closely at several examples of vintage aircraft and the role they played in aviation history.

In the Air for Sean D. Tucker’s Last Solo Season
By Kevin Burke

The dramatic photo on the front cover was taken by Kevin Burke, who has had the opportunity several times to fly in a chase plane following the daring aerial exploits of veteran air show pilot, Sean D. Tucker. It’s not an easy assignment and to get this kind of photo you need to have a good camera, plenty of experience using it and an ability to forget that you’re being held into the plane by a belt during a flight nearly as breathtaking as Sean’s.

Photographing USAF Thunderbirds’ Air Show Demonstration
By Kevin Burke

When you go to an air show, you’ll want to bring along your camera to try to freeze some of the drama for later viewing. But, there’s a trick to photographing moving objects, particularly when they’re moving at hundreds of miles per hour, at heights anywhere from 200 feet to 5,000 feet, under rapidly changing light conditions. Kevin has had a lot of experience doing so and has some tips for your next air show.

Scanning America
By Dan Veeneman
Scanning Jackson County, Mississippi

Federal Wavelengths
By Chris Parris
Atlanta Federal Mysteries and Super Bowl 53

MilCom
By Larry Van Horn N5FPW
Monitoring Venezuela’s Military

Utility Planet
By Hugh Stegman
Rejoice! WWV is Saved!

Shortwave Utility Logs
By Mike Chace-Ortiz and Hugh Stegman

VHF and Above
By Joe Lynch N6CL
ESA Astronaut Tim Peake KG5BVI and
UK Space Agency’s Principia Education Campaign

Digitally Speaking
By Cory GB Sickles WA3UVV
EMCOMM and DV Radio

Amateur Radio Insights
By Kirk Kleinschmidt NT0Z
Antennas before Amplifiers

Radio 101
By Ken Reitz KS4ZR
OTA-TV and the Mystery of HDMI

Radio Propagation
By Tomas Hood NW7US
It’s a Gray Area

The World of Shortwave Listening
By Ken Reitz KS4ZR
Shortwave Listening in the 21stCentury

The Shortwave Listener
By Fred Waterer
Shortwave Still Offers Exotic Listening

Amateur Radio Satellites
By Keith Baker KB1SF/VA3KSF
Amateur Radio Satellite Primer (Part III)

The Longwave Zone
By Kevin O’Hern Carey WB2QMY
Still Learning with SDRs!

Adventures in Radio Restoration
By Rich Post KB8TAD
James Millen and the Toy Company

Antenna Connections
Dan Farber AC0LW
Flying High Again: Aircraft Antennas

The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.

Directional antennas, multi-mode digital voice, and lousy propagation

Stories you’ll find in our February, 2019 edition:

The Development of the Directional AM Broadcast Antenna
By John Schneider W9FGH

In the early years of AM radio broadcasting, all stations utilized non-directional antennas made of wire and suspended between towers or buildings. Interference, especially at night was severe—enough to disrupt reception of the desired station—and if the frequencies of the two stations were slightly separated, there would be a heterodyne beat note. As a result, only a few widely spaced stations could operate on each of the AM broadcast channels in the entire country at night—many of which shared time on a single frequency. As antenna technologies were developed and improved in the early 1930s, a few progressive stations began experimenting with multi-element directional arrays. John gets into the details of those early experiments that led the way to today’s AM antenna arrays.

TSM Reviews: Jumbo MMDVM Hotspot
By Mark Haverstock W8MSH

Over the last few years, several hotspot interfaces have appeared on the market such as DV Mega with Raspberry Pi, DVMega with Bluestack, Shark RF OpenSpot, and DV4Mini—all hovering around the $200+ range, making them a bit pricey for all but the most dedicated digital radio users. However, a new wave of digital hot spot, manufactured in China, are finding their way onto eBay, Amazon, and other online sites. These Multi Mode Digital Voice Modem (MMDVM) boards are not developed to replace repeaters, but rather to supplement them. In areas where there is no repeater, a hotspot lets a user connect directly to a digital network via the Internet. In areas of heavy repeater use, a hotspot allows the user to access the digital network without competing for an available time slot. Mark tells us how all of this works in actuality.

Piggy Bank Ham Radio: Part 3
By Cory GB Sickles

In the third installment of his Piggy Bank Ham Radio series, Cory explains the concept of literally saving pennies for cheap adventures on the ham bands that can have much bigger payoffs. His advice includes how to assemble the most useful tools at the best possible price; how to improve your soldering skills to repair older equipment that may need only a small amount of work to be useful again; making use of off-the-shelf technology you may already have to further your amateur radio activities. Cory provides good advice for new hams and veterans of the bands alike who want to spend more time on the air and less time looking through online catalogs and wishing they were.

The Discoveries of Hans Christian Ørsted
By Georg Wiessala

The Great Danish scientist, Hans Christian Ørsted, was a pioneer of electromagnetism who paved the way for Michael Faraday (1791-1867), Bohr and others. With his brother, Anders Sandøe Ørsted (1778-1860, who became a jurist and the third Prime Minister of Denmark), Hans Christian epitomized what has been termed the “Danish Golden Age,” from the turn of the 18th Century to the mid-19th Century. It was he who was said to have coined the word “electromagnetic.” The theoretical world in which Ørsted worked was packed with adherents of opposing philosophies but it was a chance observation that allowed Ørsted to claim an important contribution to the science of electricity.

Scanning America
By Dan Veeneman
First Look: Uniden Bearcat SDS200

Federal Wavelengths
By Chris Parris
Tucson Federal Update and DoE

Milcom
By Larry Van Horn N5FPW
Aircraft Spotting in the Digital Age

Utility Planet
By Hugh Stegman
It’s Time to Expand Aero Band SELCAL

Shortwave Utility Logs
By Mike Chace-Ortiz and Hugh Stegman

Digitally Speaking
By Cory GB Sickles WA3UVV
DV Miscellany

Amateur Radio Insights
By Kirk Kleinschmidt NT0Z
Audio Equalizers—Awesome, Overlooked and Gobbledegooked!

Radio 101
By Ken Reitz KS4ZR
Shortwave Listening in Your Car

Radio Propagation
By Tomas Hood NW7US
Lousy Propagation on 40, 80 and 160 Meters

The World of Shortwave Listening
By Andrew Yoder
Government Shutdown Spurs Pirate Shortwave Activity

The Shortwave Listener
By Fred Waterer
Shortwave Radio Yesterday and Today

Amateur Radio Astronomy
By Stan Nelson KB5VL
Tracking Meteor Activity

Adventures in Radio Restoration
By Rich Post KB8TAD
EICO HF-35: A Williamson-Mullard 520 Audio Amplifier

Antenna Connections
By Dan Farber AC0LW
Stealth: An Ongoing Philosophy

The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.


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