Posts Tagged ‘Morse Code’
What was your first major receiver?
I started in the ham radio and shortwave listening hobby in 1972. By 1975, this was my first real receiver. It heard very well, and ignited my lifelong passion for radio.

The R-366/TRR-5 military receiver.
This old radio, the R-366/TRR-5, which is clearly identified on the faceplate in this picture of the military rig, had great ears. It was what I used to hone my Morse code copying skills and to get the hang of how amateur radio operators conducted communications with each other, with CW, AM, or SSB. I hope someday to own one once again.
The R-366
The R-366/TRR-5 is a significant piece of military history manufactured for the Navy Department Bureau of Ships by the Espey Manufacturing Company. Built during an era when the United States Navy required absolute reliability for ship to shore and ship to ship communications, the unit is a testament to the rugged industrial design of the mid-twentieth century. Often referred to as part of the TRR-5 receiving set, this equipment frequently incorporated high quality components and precision engineering including the gold standard Collins Radio Company designs of that period. These internal components were vital in providing the remarkable stability and selectivity needed to pull weak signals out of the dense electronic noise environment found on a crowded naval vessel. It did have heterodyne squeals on a select few frequencies, which any old tube receiver was prone to have, but those did not detract from the excellent capability of the radio.
The Service
For the sailors and radio operators serving aboard ships in the 1950s and 1960s these receivers were far more than just tools for duty. In the often cramped and isolated conditions of life at sea these radios served as a critical psychological anchor. Access to the bands meant hearing the familiar sounds of home or tuning into MARS stations where amateur radio operators facilitated phone patches that reconnected sailors with their families. This bridge to the outside world was essential for maintaining morale and supporting the mental health of military personnel who were otherwise cut off from the rhythms of civilian life for months at a time. Sitting in the radio shack and slowly tuning that large central dial while listening to the crackle of the ionosphere was a meditative escape from the constant hum of shipboard operations. Many ships would pipe ball games and news shows, or music programs, over the ships intercomms, providing health and morale to the personnel.
Operating the Radio
The tactile experience of operating this specific receiver remains vivid in my memory. The layout with its distinct knobs for selectivity phasing and BFO control was designed for the hands of a professional radio operator who needed to manipulate the signal in real time. It required a disciplined ear and a steady hand to copy Morse code through heavy atmospheric conditions but that struggle made every successful reception feel deeply rewarding. It taught me the patience and technical appreciation that have defined my amateur radio hobby for decades. Owning and using a piece of history like this represented a connection to the generations of operators who stood the watch before me.
Traveling the World…
With this historic military receiver, I discovered an entire world as a child in the mid 1970s. I spent countless nights in the quiet darkness of my room with only the warm orange and yellow glow from the vacuum tubes leaking out of the back and top grills and slots of the radio enclosure, as those hot tubes cast soft light on the ceiling and walls. That radio allowed me to travel the globe from my listening position often sitting cross-legged on the floor in front of this big rig. Those late night listening sessions, when I should have been sleeping, ignited a lifelong passion for understanding the vast and interconnected world of shortwave radio as well as medium-wave DXing. I heard International Shortwave Broadcast stations as well as AM broadcast stations from Europe, Asia, the South Pacific, the Atlantic regions, South America, Central America, and North America–all over the world! I listened to amateur radio operators on Morse code, SSB, and AM modes. Ships at sea, aircraft doing transoceanic flights, fishing vessels comms where fishing captains would chat with other boat captains, and even military communications were all at my fingertips on the dial of the radio as I listened to these exotic places by headphones. I even picked up a station from Peru, South America late one night, on the mediumwave broadcast band. That is how great that receiver could hear. Of course, I had a very excellent outdoor dipole antenna that was cut for 160 meters.
What Receiver Was Your First?
What was your first major receiver? Was it just a receiver, or was it a transceiver? When was that? What did you hear that captured your imagination? Do you still have that radio?
I hope to someday have this R-366/TRR-5, once again.
~ Happy DX!
NW7US
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.
[embedyt] https://www.youtube.com/watch?v=H-KUat5WEkU[/embedyt]
This film is a 1939 Government film scanned to 2K from a 16mm combined B/W reduction print.
The Art of DX Pileup Busting
SOME INFORMAL THOUGHTS ON WORKING CW DX
Recently, I came across some questions another amateur radio operator posed to a group of CW enthusiasts. Since I have an interest in Morse code, I thought I would explore these questions:
— begin quote —
1. When chasing some particular CW DX station needed for my DXCC punch-list, what are some things(s) that one can do to improve one’s chances of snagging that DX contact amidst a congested pileup? Is it truly the luck of the draw or roll of the dice? Or are there some time tested methods, less than obvious, that the experienced CW DX chasers have used that seem to improve one’s chances of snagging the DX contact? Yes, I’m aware that there are many variables to consider. I’m just looking for some general suggestions to improve my odds of success based on the experience of others.
2. If, let’s say, a DX station appends “UP 1” or “QSX 2” to his CQ call or just “UP” appears in a DX cluster spot listing, what is considered an acceptable amount of “UP”? I’m amazed sometimes at the amount of “UP” that I hear. LOL. Does a hefty amount of “UP” actually improve one’s chances? What does the DX op expect?
3. After a DX station sends their callsign how long should one wait to reply with one’s callsign? I hear stations respond immediately. But sometimes I hear others wait just a “bit”, and then respond to DX. And sometimes when the DX station is responding to a chosen station, other callers are STILL calling the DX op. What do most DX operators expect with regard to the response of a reply? Immediate? One-Mississippi …?
4. I hear stations reply to DX with their callsign once. Others sometimes twice. If I send my callsign twice I run the risk that the DX station has already begun his reply back to me with my sig-report while I’m still in the midst of sending my 2nd callsign reply. So … I should send my call just once?
— end quote–
Great questions! And, the answers translate over to working DX pileups on voice, too.
Here are some of my off-the-cuff remarks, based on my limited experience DXing since 1990:
(I am an avid DXer, with 8BDXCC, etc.)
1. Listen, Listen, Listen: The DX station typically does work split – the DX station on, say, 14.023 MHz, and the DX station is listening anywhere from 14.028 to 14.033 (up 5 to 10). You first, of course, need to listen to the DX station, but, also to hear the stations that are calling the DX station! The trick is to be able to hear some of the stations that are piling up on the DX, and to determine if the DX is working a station, then tunes up a little, or down a little, from the frequency on which the last caller was chosen.
Once you know this, you want to position your signal so that the DX operator tunes to or very near where you are transmitting your signal. If the DX station does not call you but continues in the same tuning direction, you reposition your transmit frequency (always in the pileup window) and try again. If you do not know where the DX station is listening next, and especially if you cannot HEAR the DX station, you are calling blind and are in for a long effort.
If you have a way to see the waterfall at and around the DX frequency, you can often see the general spread of “UP” where the callers congregate. When listening (and, let me tell you, listening is key) to the DX station, watch the waterfall for the responding caller (the station in the pile-up calling the DX), as sometimes it is very obvious who is answering the DX. Watch this exchange for a number of new callers – and get a sense of HOW the DX operator is moving through the pile-up. Anticipate where the DX might listen next. Choose that “next frequency in the pattern of movement” and use that as your calling frequency.
2. Timing your call: this takes a bit of effort. I typically listen to my chosen transmit frequency, trying to call never at the exact same time as others, on or near my calling frequency.
3. I always send my callsign TWICE… something like this:
DX: DX1ABC UP
ME: NW7US NW7US
DX: NW7US 5NN
ME: R R NW7US 5NN TU
DX: NW7US TU, DX1ABC UP
There are some fine CW-oriented DXing books, PDFs, and websites that talk about this. For instance:
http://sota-dl.bplaced.net/articles/cw_chasing_tips_for_newcomers.pdf
https://www.cadxa.org/getting-started-in-dxing.html
I hope this personal observation of mine about working a Morse code pileup is helpful in some way.
73 de NW7US
https://NW7US.us
..
Begali Intrepid
The Perfect Bug?
A New Design
- The pendulum hinge is at the rear of the key rather than the middle
- The adjustments are all based on magnets rather than springs
- The dwell for the dits has a real control, rather than using various pieces of foam, string or clips to change dwell time
- The dit contact is a sprung plunger that always remains centered on the contact rather than brushing against it at various angles
- The split lever mechanism operates at the center of the key placing the DAH and DIT contacts much closer to one another than a traditional bug
- There is less mass in the pendulum itself than a Vibroplex Bug
- It has a sprung, nylon wheel damper that doesn't clatter
- It weighs a TON (well about 6 lbs) and feels welded to the desk without having to use non-slip material or using spit to semi glue them in place (yech, yes I use spit to hold my keys to my desk)
Preparing for Use
In Use
Conclusions?
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.
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
https://NW7US.us
..
Portable Ops in Comfort
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| Working my rolling shack portable station from air-con comfort |
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| Early try with a military fiberglass pole mast |
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| Now I use a Flagpole Buddy with a 30 foot telescoping mast |
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| Gone RF fishing with a 30 foot pole and a big sinker. |
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| Palm Radio Single Paddle |
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| On the Eagle the Palm Radio Single magnetically attaches to the side |
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| Note the power and antenna connections under the table |
Benefits of the Yaesu XF-130CN 300 Hz Crystal Roofing Filter
Do You Need That Filter?
The Yaesu FT-DX10 comes standard with a 500 Hz crystal (xtal) roofing filter, but offers an optional 300 Hz roofing filter. Should you purchase the optional filter?
The 300 Hz roofing filter is twice the size of the 500 Hz filter so it must be twice as good right?
If you casually switch back and forth between the two filters on a noisy band, it sounds like the 300 Hz filter markedly improves selectivity and quiets the noise. But try this: Select the 500 Hz filter and narrow the bandwidth (using the bandwidth control) to 300 Hz, then switch to the 300 Hz filter.
When you digitally narrow the bandwidth of the 500 Hz filter to 300 Hz you will "hear" the same reduction in noise as you have cut out 200 Hz of higher frequency sound. Engaging the 300 Hz filter lowers the volume a bit (3-6 dB) due to insertion loss.
So what you are actually "hearing" when you switch back and forth between the filters without changing the digital bandwidth is the reduction of the higher frequency noise that can be accomplished using the bandwidth control alone with the 500 Hz filter.
So, from a selectivity standpointthe 300Hz filter doesn't gain you anything over using the digital filtering with the 500 Hz filter. The real benefit should come in the form of adjacent signal rejection. So let's look at that.
In the video below I demonstrate the signal rejection of a 40 dB over S9 adjacent signal to a weaker S3 - S5 signal.
From the video you can hear that there is a very small demonstrable difference in strong signal rejection when using the 300 Hz optional filter, but the difference is so small that I doubt many of us would find practical benefit over simply narrowing the DSP bandwidth while using the 500 Hz filter. Even when contesting. The digital filtering built into the FT-DX10 is really, really good when using the included 500 Hz roofing filter alone.
Yes, I spent the $200 for the optional filter thinking it would help, but I wished I had known what I do now. I would have $200 for some other nifty radio gadget to spend instead.
That's all for now.
Lower your power and raise your expectations
Richard AA4OO







































