Posts Tagged ‘radio’

Go Back In Time – Vintage Film

Turning back time to virtually witness a critical historic method of shortwave communication using the fundamental mode of continuous wave modulation. This is a film from 1944, teaching the basics of Morse code, for military comms.

What is the proper (and most efficient) technique for creating Morse code by hand, using a manual Morse code key? Ham radio operators find Morse code (and the ‘CW’ mode, or ‘Continuous Wave’ keying mode) very useful, even though Morse code is no longer required as part of the licensing process. Morse code is highly effective in weak-signal radio work. And, preppers love Morse code because it is the most efficient way to communicate when there is a major disaster that could wipe out the communications infrastructure.

While this military film is antique, the vintage information is timeless, as the material is applicable to Morse code, even today.

Credits: National Archives and Records Administration

Department of Defense. Department of the Army. Office of the Chief Signal Officer. (09/18/1947 – 02/28/1964)


Made possible by a donation from Mary Neff.

German Teletype (RTTY) Weather on HF (Shortwave) Radio

This is a video of the German Weather Broadcast from DWD, Hamburg, on shortwave (HF), using teletype (RTTY). I demonstrate two decoding software options: JWcomm32 (older), and, FLdigi. Note the in FLdigi, the “Reverse” feather is selected to properly decode the signal (in either USB or LSB, you still need to select, “Reverse”).

The radio used to receive these weather bulletins is an Icom IC-7610, using an antenna designed for 160 Meters.

RTTY is a system for broadcasting text over radio. The technology dates back to the late 1950s and seems somewhat anachronistic. Speeds are slow, even slower than NAVTEX. A similar service is the USCG service, SITOR (Simplex Teletype Over Radio) providing offshore and coastal forecasts over very wide and remote areas from the tropics to the polar regions.

There is dedicated equipment to receive RTTY and SITOR but we can receive both using a standard HF/SSB receiver with software packages such as TRUETTY and SEATTY to decode the signals.

The main advantage of RTTY/SITOR is the reception of information over an entire ocean area. The USCG also shares frequencies across multiple transmitters according to a schedule, rather like NAVTEX. The system is available over the Atlantic and Pacific including polar regions not served. For more about SITOR see the Monitoring Times link or the USCG site.

Around Western Europe and the Mediterranean, the Deutscher Wetterdienst (DWD) , the German Weather Service has accepted the responsibility to broadcast weather information for mariners on RTTY. Frequencies are in the table on the webpage at:

This video captures the RTTY transmission on 14467.3 kHz (with adjustment in the passband to center on Mark and Space as seen in the video).

DWD (Hamburg) Broadcast Content:

Some broadcasts are of raw weather observations in a WMO coded form. Otherwise, for the broadcasts include,

  • Strong wind, gale and storm warnings for German Bight, Western and Southern Baltic Sea, German North Sea and Baltic Sea coast
  • Weather forecast for the North Sea and Baltic Sea, Weather situation, forecast valid for 12 hours and outlook valid for another 12 hours
  • Weather report German North Sea and Baltic Sea coast, Weather situation and forecast valid for 12 hours.
  • Navigational warnings for North Sea, Baltic Sea and German coast
  • Weather report Norwegian Sea and Baltic Sea Route North Cape – Shetlands, The Quark – Gulf of Finland. Weather situation and time series forecast for 2 days
  • Weather report North Atlantic. Route Pentlands – Southwest Greenland. Weather situation and time series forecast for 2 days
  • Station reports North Sea and Baltic Sea
  • Weather report Western European Sea. Route Southern Ireland – Area Canarias. Weather situation and time series forecast for 2 days
  • Medium range weather report North Sea, Weather situation and time series forecast for 5 days
  • For the Mediterranean there are Station reports Mediterranean Sea
  • Weather report Mediterranean Sea (in German), Weather situation and forecast valid for 24 hours.
  • Alborán – Tunis. Weather situation and time series forecast for 2 days
  • Weather report Eastern Mediterranean Sea (in German). Route Eastern Tunis – Rhodes/Cyprus. Weather situation and time series forecast for 2 days
  • Medium range weather report Mediterranean Sea (in English), Weather situation and time series forecast for 5 days
  • Around the North Sea and the Baltic this service is a useful supplement to NAVTEX. Particularly so are the 5 day outlooks, These give wind forecast every 12 hours for the 5 day period. The values are straight from the DWD NWP model at a few grid points although these are sufficient to give an overall view and much quicker to receive than synoptic charts on radio fax.

In the Mediterranean, most valuable is the 5 day forecast which seems to be used and very highly regarded by the majority of serious cruising yachtsmen. It is a most valuable service for predicting the major strong wind systems such as Mistrals, Libeccios, Tramontanes, etc. Such winds are usually well predicted 4 and often 5 days ahead. Conversely, I have never found the 24 hour forecast to be much use. For this period, the French, Spanish and even the Italian NAVTEX broadcasts are to be preferred.

Modern Amateur Radio Hobby – An Introduction

This video is an introduction to an international public-service and technology hobby known as ‘amateur radio’ (or ‘ham radio’).

Amateur radio (also called ham radio) describes the use of radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communication. The term “amateur” is used to specify “a duly-authorized person interested in radioelectric practice with a purely personal aim and without pecuniary interest;” (either direct monetary or other similar rewards) and to differentiate it from commercial broadcasting, public safety (such as police and fire), or professional two-way radio services (such as maritime, aviation, taxis, etc.).

The amateur radio service (amateur service and amateur-satellite service) is established by the International Telecommunication Union (ITU) through the Radio Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual stations licenses with an identifying call sign. Prospective amateur operators are tested for their understanding of key concepts in electronics and the host government’s radio regulations. Radio amateurs use a variety of voice, text, image, and data communications modes and have access to frequency allocations throughout the RF spectrum to enable communication across a city, region, country, continent, the world, or even into space.

Amateur radio is officially represented and coordinated by the International Amateur Radio Union (IARU), which is organized in three regions and has as its members the national amateur radio societies which exist in most countries. According to an estimate made in 2011 by the American Radio Relay League, two million people throughout the world are regularly involved with amateur radio. About 830,000 amateur radio stations are located in IARU Region 2 (the Americas) followed by IARU Region 3 (South and East Asia and the Pacific Ocean) with about 750,000 stations. A significantly smaller number, about 400,000, are located in IARU Region 1 (Europe, Middle East, CIS, Africa).

Activities and practices

The expansive diversity found in the amateur radio hobby attracts practitioners who have a wide range of interests. Many hams begin with a fascination of radio communication and then combine other personal interests to make the pursuit of the hobby rewarding. Some of the focal areas amateurs pursue include radio contesting, radio propagation study, public service communication, technical experimentation, and computer networking. But, that is just a sampling of interest areas found in the hobby.

Amateur radio operators use various modes of transmission to communicate. The two most common modes for voice transmissions are frequency modulation (FM) and single sideband (SSB). The FM mode offers high-quality audio signals, while SSB is better at long distance communication when bandwidth is restricted.

Modern personal computers have encouraged the use of digital modes such as radioteletype (RTTY) which previously required cumbersome mechanical equipment. Hams led the development of packet radio in the 1970s, which has employed protocols such as AX.25 and TCP/IP. Specialized digital modes such as PSK31 allow real-time, low-power communications on the shortwave bands. More robust digital modes have been invented and improved, including such modes as Olivia, JT65, and WSPR.

NASA astronaut Col. Doug Wheelock, KF5BOC, Expedition 24 flight engineer, operates the NA1SS ham radio station in the Zvezda Service Module of the International Space Station. Equipment is a Kenwood TM-D700E transceiver.

Amateur radio operators, using battery- or generator-powered equipment, often provide essential communications services when regular channels are unavailable due to natural disasters or other disruptive events.

This video comes to us via Canada, and is used by permission from Bernard Bouchard – / ve2sms – The original video was published on Feb 28, 2013.- Website is

Voici maintenant, la version complète du documentaire «La radioamateur» d’une durée de 11 minutes. On y aborde toutes les activités sur le monde de la radioamateur. Ce vidéo a été produit par le Club Radioamateur VE2CWQ / Canwarn-Québec. Pour information:

Connect with me at

USA Amateur Radio information:

1939 Film: Morse Code on HF in New Zealand (Historical)

Before modern radio broadcasting, the trails were being blazed both in public broadcast, but also critical links out of the local area. Here’s a side-look back in time…. in this 1939 Film: New Zealand Shortwave Communications; Morse code (CW)

The romance of the radiotelegraph service (in this video, the service in New Zealand) is a fascinating aspect of communication history. The use of shortwave, longwave, and medium frequency spectrum for communication, particularly through Morse code, played a significant role in connecting people across vast distances. This service utilized the high-frequency spectrum known as “shortwave” (from 3 MHz up to 30 MHz) as well as the longwave (30 kHz to 300 kHz) and medium frequency spectrum (300 kHz to 3 MHz).

This short film is from 1939, and captures the essence of communication at that time in history, to and from New Zealand using shortwaves and Morse code. It showcases the importance of the radiotelegraph service in enabling long-distance communication during that era. The transition from Morse code via spark-gap communications to continuous wave (CW) modulation marked a significant advancement in the technology and efficiency of radio communication.

It’s incredible to see how technology has evolved over the years, transforming the way we communicate and connect with each other globally. Films like these provide a glimpse into the past and remind us of the ingenuity and dedication of those who worked in the radiotelegraph service to ensure effective communication across the seas.

This film is a 1939 Government film scanned to 2K from a 16mm combined B/W reduction print.

New to Amateur Radio? What is a Repeater?

If you have not yet explored ham radio repeaters, this might be interesting to you.

What is an amateur radio repeater and how do they work?

In this video, with a non-amateur-radio viewer in mind, I chat about the very basic concepts of a repeater.

It is filmed in a relaxed, “ride along with me,” format.

Want to learn more about ham radio (amateur radio)?

Marine Radiofax Weather Charts Via Shortwave Radio – WEFAX

Weather out over oceans?  That, and more.

More than international broadcast stations and amateur radio operators exist on the shortwave radio spectrum.  For instance, any non-broadcast signal that is not amateur radio is often lumped together into a category known as Utility Radio, abbreviated, UTE.  To dig deeper into UTE activity, you could check out the UDXF – the Utility DX Forum, located here:

Utility stations (UTE) are quite common, from marine (ships, fishing vessels, etc.), transoceanic air traffic (international passenger or cargo jets and other aeronautical trans-oceanic radio traffic), to military radio (weather, coordination, and much more).  UTE is a rich subdomain of the radio experience.

As an amateur radio operator, I listen to and monitor utility stations on shortwave, at times when not operating as an amateur radio station.  I check weather for air traffic or for marine traffic, because it helps me see the larger-scale weather patterns.

Sample Weather Satellite Picture via Shortwave

One of the captured weather images via shortwave radio.

Here is a video I made of my reception of weather charts via shortwave radio from radio station NMC, at Point Reyes, CA, using FLdigi software to receive these weather fax transmissions:

WEFAX 22.527 MHz on 2024 JUNE 14

This video is a screen and sound capture of my reception of weather charts and images by shortwave radio, from a station in California running about 4 kilowatts of RF power. This HF WEFAX (Weather Facsimile) service is on every day for ship (marine) weather dissemination so that ships out on the ocean can get weather charts and images not by satellite, but by receiving shortwave signals.

Below is a snippet from the published schedule from Point Reyes WEFAX Radio, callsign NMC, as follows:

22527 kHz – tune offset 1.9 kHz (see note, below)

----- --------------------------------
19:53 96HR 500MB FORECAST

The above snippet of the NMC chart transmission list is from the page, “NMC Point Reyes, Marine Radiofax Broadcast Schedule” found at:

One of the captured weather images via shortwave radio.

One of the captured weather images via shortwave radio.


Here is a detailed description of the weather charts, and online access is at:

Note: In the video, you see that I am tuned to 22.526 USB thus I was tuned to 22526 kHz USB, based on this: “Unless otherwise stated, assigned frequencies are shown, for carrier frequency subtract 1.9 kHz. Typically dedicated radiofax receivers use assigned frequencies, while receivers or transceivers, connected to external recorders or PC’s, are operated in the upper sideband (USB) mode using carrier frequencies.”


April 12, 2024


International Morse Code Day (April 27)

Morse Code Day on April 27 (every year) honors one of the inventers of the Morse code, Samuel Morse, who was born on this day in 1791.

Morse Code Day on April 27 (every year) honors one of the inventers of the Morse code, Samuel Morse, who was born on this day in 1791.

Happy Morse Code Day, April 27 (every year).

Samuel Finley Breese Morse (April 27, 1791 – April 2, 1872) was an American inventor and painter. After having established his reputation as a portrait painter, in his middle age Morse contributed to the invention of a single-wire telegraph system based on European telegraphs. He was a co-developer of Morse code and helped to develop the commercial use of telegraphy.

Alfred Vail developed the dot-dash structure, and Leonard Gale along with Vail was instrumental in developing the mechanical receiving apparatus for code.

Samuel Morse gets most of the credit because of his work in promoting this code as a viable means of communication. Morse code is still used now. Amateur radio is one of the communities in which Morse code is popular and in daily use.

73 de NW7US dit dit



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