Tracing the Development of the AM Broadcast Transmitter
John F. Schneider W9FGH
In the Beginning, there was King Spark. There were a few early attempts at using spark equipment to transmit the human voice. This was because a spark signal consists of a continuous sequence of decaying waves, called “damped waves.” The signal faded in intensity as the energy of each spark dissipated, until it was replaced by a new signal from the next spark. In the early 1900s, there were only two devices that were capable of generating a continuous wave – an arc transmitter and a high-frequency alternator. But it was the invention of the “Audion” triode vacuum tube by Lee de Forest in 1906 that created a revolution in radio communications. Its ability to function as both an oscillator and amplifier opened doors to the creation of a practical all-electronic speech transmitter. John takes a detailed look at the evolution of the AM broadcast transmitter.
Has it Really Been a Decade!?
By Troy J. Simpson W9KVR
There’s nothing easy about teaching school anywhere but teaching, coaching, keeping a school amateur radio club going, being a dad and a husband makes time really fly. So much so that Glenn Raymond Middle School teacher, Troy Simpson, hadn’t realized their club station license was already up for renewal until he received the notice from the FCC. Troy recaps just the last few years of this very active and successful amateur radio school club as he prepares this month for another School Club Roundup.
SDR Report Part 3: From High-End SDR Receivers to SDR Transceivers
By Thomas Witherspoon K4SWL
Part one of our series on Software Defined Radios (SDRs), which appeared in the June issue, focused on the nomenclature and components of a functioning SDR system. Part two, in the July issue, took a look at some affordable SDR station options that would propel you into the world of SDRs for less than $200 US. This month, Thomas dives a little deeper into the SDR rabbit hole, and investigates higher-end SDRs as well as ham radio transceivers with embedded SDRs that include high-ticket rigs that have intel-agency specs and capabilities you won’t find in any analog radio at any price.
A Visit to the Tokyo Ham Fair 2018
By Keith Baker KB1SF/VA3KSF
Once again, Keith was asked to join the Dayton Amateur Radio Association team in a trip to Japan to attend the annual Tokyo Ham Fair, which is sponsored by the Japan Amateur Radio League (JARL). As Secretary-Treasurer of AMSAT North America, Keith would be doing double duty during this trip. And, as a regular contributor to TSM, Keith nailed the trifecta with this photo essay of that trip. Keith renewed many old acquaintances, got up close and personal with new ham equipment and enjoyed handing out goodies to everyone he saw.
Scanning America
By Dan Veeneman
Hialeah, Florida, and a Public Service Radio Feud
Federal Wavelengths
By Chris Parris
Hurricane Florence Response
Milcom
By Larry Van Horn N5FPW
Monitoring the US Coast Guard and the COTHEN HF Radio Network
Utility World
By Hugh Stegman
US Coast Guard Mobilizes for Hurricane Florence
Shortwave Utility Logs
By Hugh Stegman and Mike Chace-Ortiz
VHF and Above
By Joe Lynch N6CL
International Space Station Astronauts are Calling CQ Students
Digitally Speaking
By Cory GB Sickles WA3UVV
Nothing Changes if Nothing Changes
Amateur Radio Insights
By Kirk Kleinschmidt NT0Z
Transmit Audio—How’s Your Sound?
Radio 101
By Ken Reitz KS4ZR
Viasat: Help for Rural Broadband Access
The World of Shortwave Listening
By Andrew Yoder
US and International Pirate Shortwave Broadcasters
The Shortwave Listener
By Fred Waterer
Creepy October Shortwave Programming
Maritime Monitoring
By Ron Walsh VE3GO
Stormy Weather and Changing Times
The Longwave Zone
By Kevin O’Hern Carey WB2QMY
SDR, Step One
Adventures in Restoration
By Rich Post KB8TAD
Reviving a Comanche: The Siltronix 1011D
Antenna Connections
By Dan Farber AC0LW
Artificial Ground, Part Two
Radio Horizons
Review: National Radio Club’s 39thEdition AM Radio Log
By Larry Van Horn N5FPW