Posts Tagged ‘Morse Code’
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
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
|Working my rolling shack portable station from air-con comfort|
|Early try with a military fiberglass pole mast|
|Now I use a Flagpole Buddy with a 30 foot telescoping mast|
|Gone RF fishing with a 30 foot pole and a big sinker.|
|Palm Radio Single Paddle|
|On the Eagle the Palm Radio Single magnetically attaches to the side|
|Note the power and antenna connections under the table|
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
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“
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
I have a story for you. All of it is true, but I have not changed my name.
Wow! I am always amazed at those moments in my amateur radio hobby when spontaneous joy is had by unexpected events.
On Thursday, 14-April-2022, at about 17:30 Universal Time (UT), the unexpected occurred, and it started by accident.
I have been reorganizing my radio shack. Once I moved my main transceiver (the Icom IC-7610) from one desk to another, and had it back in operation, I left it tuned to a random frequency, in the CW mode. It was just sitting there, hissing away with the typical shortwave sounds of a frequency on which no one was transmitting. And me? I was going about reorganizing my radio shack.
After a while, I heard the start of a Morse-code CW signal; the operator was sending a CQ call–a transmission that invites a response from anyone who wishes to have a QSO with the calling station. What I heard was, “CQ CQ DE EP2ABS EP2ABS…”
NOTE: This transceiver, my Icom IC-7610, is listening with the new antenna—the 254-foot doublet up at 80 feet–that was raised up into the air here at my QTH by a fine crew from Hams in the Air.
I looked up EP2ABS on QRZ dot com, because I did not know from what country/entity the EP2 prefix on callsigns belongs. I was excited to see that EP2 is from Iran!
I started answering his CQ call, “DE NW7US NW7US,” for at least ten minutes; each time he sent his CQ, I answered. Finally, I heard him answering me, “NW7US NW7US DE EP2ABS 5NN…”
I answered back, sending my signal report, “5NN 5NN DE NW7US TU”
Soon after that simple exchange, he confirmed our QSO by posting our QSO to Logbook of the World (LotW).
Thus, by accident–as I had simply left the transceiver tuned to a randomly-selected frequency and stayed on that frequency listening while doing my chores–I heard the Iranian station calling CQ. What are the odds!?!?
This is my first QSO with Iran, another All Time New One (ATNO). How cool!
Note: This is a testimony to the work from the crew that did the fine work of getting this antenna installed. Here is a video presented by Hams on the Air:
73 de NW7US dit dit
A VISUAL + AUDIO AIR CHECK OF DIGITAL MODE FT8 QSOs, ON THE 30-METER BAND
Here is a video capture of the reception and transmission of many digital FT8-mode amateur radio high-frequency (HF; Shortwave) communication signals. This video is a front-seat view of the software operation performed at the radio room of amateur radio operator, NW7US, Tomas Hood.
The software packages demonstrated are installed and operational on a modern personal computer. The computer is connected to an Icom IC-7610 radio transceiver, controlled by the software. While there is no narration in the video, the video provides an opportunity for you to see first-hand how typical FT8 operations are performed. The signals can be heard.
The frequency used for the FT8 communication in this video is on or about 10.136 MHz, in the 30-Meter shortwave amateur radio allocation (or, band). As can be seen, the 30-Meter band was active at this time of day (0720 UTC, onward–local nighttime).
In this video you see (and hear) NW7US make two-way contacts, or QSOs, with stations from around the country and the world.
There are amateur radio operators within the amateur radio community who regard the FT8 digital mode (FT8 stands for “Franke-Taylor design, 8-FSK modulation“, and refers to the mode created by Joe Taylor, K1JT and Steve Franke, K9AN) as robotic (automatic, automated, and unattended) computer-to-computer communications, and not ‘true’ human communications–thus negating the spirit of ham radio. In other words, FT8, in their opinion, is not real amateur radio. While they pontificate about supposed automated computer communications, many of those holding this position have not installed and configured the software, nor tried communicating with the FT8 digital mode. They have perhaps formed their anti-FT8 opinion in a vacuum of knowledge. (This writer has other issues with FT8, but not on this point–see below)
As you watch the video linked in this article, consider these concepts:
+ A QSO is defined (as per common knowledge–see below) as the exchange of at least the minimum information needed as set by the requirements of a particular award, or, as is defined by law–for instance, a QSO would have at least an exchange of the legal call sign assigned to the radio station and/or control operator, the location of the station making the transmission, and a signal report of some kind about the signal received from the other transmitter at the other end of the QSO.
+ Just how much human involvement is required to make a full FT8 QSO? Does WSJT-X software run all by itself, with no human control? Is WSJT-X a robot, in the sense that it picks a frequency, then initiates or answers a CQ call automatically, or is it just powerful digital-mode software that still requires human control?
The video was captured from the screen of the PC running the following software packages interacting together as a system:
+ WSJT-X: The primary software featuring the digital mode, FT8. (See below for some background on WSJT-X software.)
+ JTAlert: Provides several audio and visual alert types based on decoded Callsigns within WSJT-X.
+ Log4OM, Version 2: A full-featured logging program, which integrates well with WSJT-X and JTAlert.
+ Win4IcomSuite: A full-featured radio controlling program which can remote control rigs, and provide control through virtual communication port-sharing.
+ Com0Com: The Null-modem emulator allows you to create an unlimited number of virtual COM port pairs and use any pair to connect one COM port based application to another. Each COM port pair provides two COM ports. The output to one port is the input from other port and vice versa.
As mentioned, above, the radio used for the communication of FT8 at the station, NW7US, is an Icom IC-7610 transceiver. The antenna is an off-center fed dipole that is over 200 feet in total length (end-to-end measurement).
WSJT-X is a computer program used for weak-signal radio communication between amateur radio operators, or used by Shortwave Radio Listeners (SWLers; SWL) interested in monitoring the FT8 digital communications between amateur radio operators. The program was initially written by Joe Taylor, K1JT with Steve Franke, K9AN, but is now open source and is developed by a small team. The digital signal processing techniques in WSJT-X make it substantially easier for amateur radio operators to employ esoteric propagation modes, such as high-speed meteor scatter and moonbounce.
WSJT-X implements communication protocols or “modes” called FST4, FST4W, FT4, FT8, JT4, JT9, JT65, Q65, MSK144, and WSPR, as well as one called Echo for detecting and measuring your own radio signals reflected from the Moon. These modes were all designed for making reliable, confirmed QSOs under extreme weak-signal conditions. JT4, JT9, and JT65 use nearly identical message structure and source encoding (the efficient compression of standard messages used for minimal QSOs). They use timed 60-second Transmit/Rreceive (T/R) sequences synchronized with UTC (Universal Time, Coordinated). JT4 and JT65 were designed for Earth-Moon-Earth communications (EME, or, moonbounce) on the Very-High Frequency (VHF), Ultra-High Frequency (UHF) and microwave bands. JT9 is optimized for the Medium-Frequency (MF) and High-Frequency (HF) bands. It is about 2 dB more sensitive than JT65 while using less than 10% of the bandwidth. Q65 offers submodes with a wide range of T/R sequence lengths and tone spacings.FT4 and FT8 are operationally similar but use T/R cycles only 7.5 and 15 seconds long, respectively. MSK144 is designed for Meteor Scatter on the VHF bands. These modes offer enhanced message formats with support for nonstandard call signs and some popular contests. (The MSK in MSK144 stands for, Multiple Frequency Shift Keying.)
FST4 and FST4W are designed particularly for the Low-Frequency (LF) and MF bands. On these bands, their fundamental sensitivities are better than other WSJT-X modes with the same sequence lengths, approaching the theoretical limits for their rates of information throughput. FST4 is optimized for two-way QSOs, while FST4W is for quasi-beacon transmissions of WSPR-style messages. FST4 and FST4W do not require the strict, independent time synchronization and phase locking of modes like EbNaut.
As described more fully on its own page, WSPR mode implements a protocol designed for probing potential propagation paths with low-power transmissions. WSPR is fully implemented within WSJT-X, including programmable band-hopping.
What is a QSO?
Under the title, CONTACTS, at the Sierra Foothills Amateur Radio Club’s 2014 Technician Class webpage, https://www.hsdivers.com/Ham/Mod15.html, they teach,
An amateur radio contact (called a QSO), is an exchange of info between two amateur radio stations. The exchange usually consists of an initial call (CQ = call to all stations). Then, a response from another amateur radio operator, and usually at least a signal report.
Contacts can be limited to just a minimal exchange of call signs & signal reports generally between amateurs previously unknown to each other. Very short contacts are usually done only during contests while longer, extended ‘rag chews’ may be between newly met friends with some common interest or someone you have known for a long time.
Wikipedia has an entry for QSO, too.
My Issue With FT8 and WSJT-X
I have written in the past, on this website, about an issue that came about during the course of the development of the WSJT-X software package. The development team decided to widen the slice of ‘default’ (pre-programmed) frequencies on which to operate FT8. The issue was how the choice of new frequencies was made, and what choices were implemented in an upcoming software release. Read more about all of this, in these three articles:
Has this issue been resolved? For now, yes. There appears to be more coordination between interested groups, and the proposed new frequencies were removed from the software defaults in WSJT-X. At least, up to this point, at the time of publishing this article.