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.

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

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 The Perfect Bug?

BUT... If we are ham radio operators regularly doing CW, then we spend a lot of time with a morse key under our hand.  I've said this previously, but when you are a CW operator you touch your key more than anything else related to the hobby.  You are moving it many hundreds to thousands of times as you send code.  Your keying becomes part of you and you are intrinsically linked with the ease or difficulty of operating the key for hours at a time.

A New Design

I've not had the chance to try the GHD fully automatic bugs, nor their bugs that use optical contacts.  That would be interesting, but they still fundamentally follow the Vibroplex model.

Preparing for Use

The Intrepid ships with a cable but there's nothing to plug it into on the key.  It's up to the owner to solder the connections.  I understand that some transceivers require different plug wiring but in general they are fairly common.  Be prepared to spend some time soldering under the key to wire it up.

I had some spare 1/8" plugs for projects, and with some heat shrink tubing and a couple pieces of wire I created a tidy connector for the male to male cable shipped with the key.

In Use

I spent about 2 hours practice sending into the practice oscillator that I built.   I had a Vibroplex Deluxe Bug next to it that I alternated with.  The range of DIT speeds on the Intrepid is impressive.  Other makers like Vizkey have created bugs with a similar range of adjustment, and the Deluxe Bug I use has a Vari-Speed that can match the Intrepids speed range, bu the Intrepid is easier to quickly adjust and more importantly can be done one-handed.  It will comfortably go from about 15 wpm up to 35 wpm and with the dwell adjustment makes changing speeds and keeping the DIT dwell correct, is singular.  I don't think any bug can match it in that respect.

It did require a change in how I operate.  The Vibroplex Bug fingerpieces stick out further and I have the habit of placing my index finger out over the top of the Bug.  The Intrepid doesn't allow for that.  I have to curl my index finger down to avoid hitting the bracing for the pendulum.

Because there is less mass in the pendulum it operates with a much lighter touch than Vibroplex Bug.  The pendulm movement is initated with less force and due to the isolation of the pendulum from the paddles you don't feel the pendulum moving as you do with a Vibroplex.  I kinda like the feedback I get from Vibroplex pendulum.  The Intrepid feels more like a single paddle key with an electronic keyer than a bug.

Because of the how the lever is split in the middle, the actual DAH contact is almost dead center in the key rather than toward the front.  It is far closer to the DIT contact than a bug.  I have no way to describe it other than to say it feels as if the DAH and DIT operations are more similar than they are different.

I tend to pivot at my wrist when I operate a Vibroplex bug, to control the timing of DIT to DAH transitions.  That doesn't seem to be as necessary with the Intrepid.  Again, it feels more like a paddle than a Bug.

The DIT contact is a sprung plunger that is always centered.  This is one of the biggest problem areas on a Vibroplex Bug and Begali has masterfully designed the proper contact.  Most Bug operators spend more time adjusting the U-spring to try and get proper contact than any other part of the key.  I assume this level of precision is just not something that Vibroplex wanted to spend the time on in manufacturing.

You'll notice there are spare holes.  I assume they are to allow the frame to be used for left handed operation.

The weights are easy to adjust but I have found that the set screws don't bite the pendulum as firmly as a Vibroplex bug and I have had them come loose a few times. When they accidently come loose they flop to one side and touch the frame, completing the circuit, resulting in a continous carrier. I'm a bit concerned about leaving the bug connected unattended to my tranceiver and having one flop over into transmit while I'm not at the station.

The laser etching is nicely done.  The model name can appear, white, gray or black depending on the angle of light.

The pendulum is hinged at the back of the key, making easy access to the adjustment weights.

Conclusions?

This is a very fine piece of engineering.  It will take me months to decide if stick with it over a Vibroplex Bug, but for now I'm thinking it was a fine birthday gift.

That's all for now

So lower your power and raise your expectations.

Rich, AA4OO https://hamradioqrp.com

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
https://NW7US.us

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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

https://www.hamradioqrp.com

There is a new book from a fellow Morse code amateur radio operator, Chris Rutkowski (NW6V), about “Learning, Living, and Loving Morse Code (in a Digital World).” NICE!

Title: “The CW Way of Life“
link: https://amzn.to/3Tm3KfD

I received a new book! Here it is, at my radio shack operations desk, at NW7US radio station.

Already, I think it rivals any other book on the topic, including “The Art and Skill of…,” or, “The Zen of…”

It is not, however, meant to replace, but to augment, what is available. But, it is a complete guide, including a “work book” section (nearly half of the book?) on how to improve your skill. Really good stuff, but I’m only in one day.

73 de NW7US dit dit
https://nw7us.us

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