I've had two good contacts VK3-VK5 using FreeDV RADE1 today. Quite a lot of stations on air.
It would be good to have a regular net for Australian stations (and anyone else who can hear us). To start with I suggest Sunday mornings from 11:00am Eastern time.
Speaking of FreeDV RADEV1, there's a great intro and reception demo from popular YouTube channel Tech Minds:
At one point he says "...the new RAIDV1 mode .. in my opinion has to be the best sounding digital mode I've heard to date." Nice.
Interestingly it also picked up some signals while in flight either during taking off and when coming in to land. I don't think it saw any at cruising altitude.
There was never a good enough connection for a direct message but I did see some traffic on the default channel.
Meshtastic is built on top of LoRa and is capable of amazing range, mostly line of sight. I have much to learn about this technology but the idea of having a way to communicate, either direct or via a mesh network without internet or cell phone coverage is interesting. A lot of nodes are named after the callsign of the ham that owns them.
Artificial Intelligence is the biggest story in tech at the moment. But there are down-sides and unexpected consequences.
One of them has a new name “AI Slop”. In other news, incredible remuneration packages are being offered to attract AI researchers to change jobs.
Peter Marks, a software developer and technology commentator from Access Informatics, joined Dom Knight on Nightlife to discuss the latest news in technology.
https://www.abc.net.au/listen/programs/nightlife/nightlife-tech-talk-with-peter-marks/105483494
Graeme, VK3CDO, is a friend from the Macedon Ranges Amateur Radio Club. He often shares his knowledge of bushcraft and this weekend we headed off to the Leanganook Campground in the Mount Alexander Regional Park. I took some wire, a squid pole and an UNUN to use with a KX3.
I had a few contacts and registered with POTA.app but really didn't spend much time at it. Enough to confirm that my unun allowed the radio to easily tune up the end fed wire. It was fairly cold and we spent some time, aside from chatting, cooking various delights. (Fried Spam in this case).
My tent worked out well but I'm glad I put a space blanket underneath as the ground was cold.
Graeme has some interesting skills, in particular, he appears to be able to make fire from almost nothing. First he used magnesium to get the fire going.
To top that, he used just a flint and a little piece of scorched cloth to quickly make fire.
It's a nice campsite with lots of space. Being a Friday night I didn't expect many other people but a few did turn up.
I talked about the FreeDV project and demonstrated one of the best performing modes, 700D with its hand crafted (by David, VK5DGR) codec and modulation and then compared it with the new Radio Autoencoder (RADE) which uses machine learning to transmit amazing sounding voice over an RF bandwidth of about 1.5kHz.
There are many applications of machine learning in the amateur radio world that come to mind including:
Today I caught a train from Southern Cross bound for Bendigo. At Footscray a man got on. He looked confused and clearly had almost no English. He was asking if this train went somewhere but we couldn't work out where he meant.
Several passengers tried to figure out what he wanted and when we finally figured out that he wanted to go to Melbourne it was too late, the doors had locked and we were under way north.
Unfortunately for him, this was an express and the next stop was Sunbury, about 40km away.
He slumped into the seat next to me and I showed him on the map where we were headed. He said he had just arrived from Iran and was going to meet his boss. I said I was sorry to hear what is happening over there. Talking to the boss on speakerphone, he explained he'd caught the wrong train. The guy on the other side offered to pick him up! I explained that that might not be the best approach, better to catch the train back at Sunbury.
He asked if I was a technician? I said yes and he told me he was working for someone who worked for someone who was a technician.
The conductor came through checking MyKi cards and my new friend pulled out an infringement notice he'd been given earlier for not having a ticket. (He seemed to think that was a ticket). I spoke with the conductor on his behalf and explained the situation. He kindly let it pass.
When we got to Sunbury a bunch of fellow passengers got up and pointed to where he should go and explained what colour train he should catch to get back to Southern Cross. It was heartwarming to see.
Our train system is confusing, even for me, I can't imagine how hard it would be for a visitor with little or no English. Signs are poor, trains leave Southern Cross on different platforms and you can't find out from within the ticketed area.
I was proud of my fellow Australians today and their open and helpful attitude to a new Australian.
I vividly remember seeing a Macintosh computer for the first time.
At the time I was heavily into CP/M and WordStar. At work we produced a newsletter by printing text columns on a daisy wheel printer. Headings were made by rubbing letters from Letraset. Photos were turned to dots with a high contrast process camera with a transparent dot screen. The pieces were cut up and pasted together.
When I saw a Macintosh with a graphical screen that showed the fonts and graphics as they would appear I was stunned.
Later I learned that it was a programmer called Bill Atkinson who was one of the very clever people who managed to make all this work in the constrained environment of those early machines. Bill wrote low level graphics code that was incredibly efficient. "QuickDraw" doesn't fully capture the achievement. He wrote MacPaint, with its box of tools including the pencil and "FatBits" which influenced all the bit map editors that followed including Photoshop and friends.
Even later, Bill created HyperCard, a user friendly development environment that could be used by almost any computer user. I loved it.
I went to a MacWorld expo in the early 90s. (This is before Apple withdrew to have their own events). To get a seat in the front row for Bill's talk I attended the session before and claimed my seat. He walked in clutching a bunch of gear strung together with SCSI cables.
He told stories about his work including the ImageWriter printer but also talked about the work he'd done to improve the dot pattern that could turn a greyscale image into a pattern of dots that smoothly simulated it. "Atkinson Dithering" it came to be known. He said that one day, when he was working on it, a colleague came to the door of his office and, seeing a nice greyscale image on his Mac's screen - commented that it was great that Apple was going to release a greyscale screen Mac! (Of course, they weren't but the dithering looked very real from a short distance away).
Bill was a visual person. I have a beautiful book of photographs of textures from nature that he published.
Thank you Bill.
New analysis from Mary Meeker finds that we are in the AI boom.
Also a look at the merger between OpenAI and ex-Apple head of design Jony Ive's io.
GUEST: Peter Marks, a software developer and technology commentator from Access Informatics. Listen here.
Like many people I was very excited by QRP-Labs work to bring sideband to the excellent, compact, high performance, digital rig, the QMX. I ordered a built version and have been using it in the field.
My setup, in a small waterproof box is quite compact but I plan to put together a portable radio with a QMX, rechargeable battery and some sort of antenna tuner. For this project I ordered the kit version and have now completed construction. It's a dense six layer board. The surface mount components are all pre-soldered so most of the work is toroids and connectors.
The QMX has built-in diagnostics, including RF bandpass and low pass filters. After my build I could see some problems all of which were due to me not managing to solder to enamelled wire. At times, inspection under high magnification revealed a solder joint where the solder seems strongly repelled by the wire. After a bit of debugging the radio is working well.
On the bench I run it from 12.0V via a linear regulator (I built the 12 not 9V version). (My bench supply of 13.8V is too high. I get 5W out on 80m and about 4W on 40 and 20m. Performance as a WSPR transceiver is really excellent.
If you run in to trouble there's some great resources including Hans' troubleshooting guide which includes a faultfinding log of fixes he's needed.
Also there is an active QRPlabs discussion group where people help each other. I've enjoyed this kit very much and it's a really wonderful radio.
I've been running it receiving and transmitting WSPR almost continuously for about a week. Rock solid. Sometimes reception of my signal is amazing (when there aren't solar flares that kill the bands). Here's a single transmission on 40m reported by 94 stations:
It also receives exceptionally well.
"Season Two of On the Media’s Peabody-winning series The Divided Dial is the untold story of shortwave radio: the way-less-listened to but way-farther-reaching cousin of AM and FM radio. The medium was once heralded as a utopian, international, and instantaneous mass communication tool — a sort of internet-before-the-internet. But like the internet, it also took a turn for the chaotic. And like AM and FM talk radio, it also went hard to the right, with extremists and cults still finding a home on the shortwaves".
THE DIVIDED DIAL EPISODE 1: Fishing In The Night
THE DIVIDED DIAL EPISODE 2: You Must Form Your Militia Units
THE DIVIDED DIAL EPISODE 3: World's Last Chance Radio
THE DIVIDED DIAL EPISODE 4: Wall St. Wants Your Airwaves
First I've heard of The Shortwave Modernisation Coalition which proposes to use shortwave for high speed trading.
I think there is a role for shortwave broadcasting but today I think it should broadcast a hard to jam, easy to receive digital data format.
Thanks to Thomas at The SWLing Post for drawing this to my attention. ABC Radio National, of which I'm a past contributor, has a documentary program called Rear Vision and this week they have a program about the demise of VOA which most of us will be familiar with from our lifetime of shortwave listening.
It's a really well done program with archival material that triggered great nostalgia as a long term listener.
"The US funded international news network Voice of America started broadcasting into Germany in 1942.
It now broadcasts in nearly 50 languages to more than 350 million people around the world.
But in March this year, US President Donald Trump signed an executive order dismantling the US Agency for Global Media - the independent government body that oversees Voice of America.
Now, Voice of America has been silenced for the first time in 83 years.
Guests:
Patsy Widakuswara is Voice of America's White House Bureau Chief and lead plaintiff in VOA's legal case against the Trump Administration.
Dr Nick Cull is Professor of Public Diplomacy at the University of Southern California, Annenberg, and he specialises in the historic role of communication in foreign policy.
Dr Kate Wright is Associate Professor of Media and Communications at the University of Edinburgh and co-author of Capturing News, Capturing Democracy: Trump and the Voice of America by Kate Wright, Martin Scott & Mel Bunce
Produced and presented by Kirsti Melville".
Great work!
The VFO is an Arduino nano and Si5351. IF is at 9Mhz and uses a crystal filter board sourced from AliExpress. Interestingly there is RF preselection using electronically switched capacitors and a varactor diode.
Audio output is an LM386. There's AGC and the radio even has squelch.
What is, perhaps, missing is AM reception.
It is wonderful to see such a project in Silicon Chip.
Peter Marks, a software developer and technology commentator from Access Informatics, joined Chris Taylor on Nightlife to discuss the latest news in technology.
https://www.abc.net.au/listen/programs/nightlife/nightlife-tech-talk-with-peter-marks/105315754
It was good to meet Chris Taylor who's filling in while Philip Clark is on leave. Chris was one of the Chaser gang and I fondly remember watching VHS cassettes of CNNNN when I worked at CNN 25 years ago.
I've been staying in Tasmania this week, on the north coast, near Devonport and naturally I wanted to bring some sort of radio gear along. The QRP-Labs QMX recently added the ability to transmit sideband. I've had a few contacts with this and reports are good. The QMX (and QDX) are particularly good at FSK modes like WSPR I think due to the direct synthesis rather than audio mixing.
My travel case is quite small and fits everything I need including a pill bottle microphone.
The station was set up overlooking the ocean with a 29' wire pretty much just resting on some bushes.
Operation was on 40m at first but 20m was the standout. I was heard as far away as Europe in the first transmission.
I'm embaressed to admit that the very compact tuner was purchased from China and is clearly a copy of the QRP Guys' Ununtenna Plus. I have ordered the real thing which they say has much better quality toroids in it. The design is good and it's the most compact antenna tuner I can carry with me.
The QMX has a built in tuning mode with SWR display but I find nulling the LED on the tuner is easier.
At first I tried operating inside the house with the wire running out through a metal sliding glass door but I couldn't get it to tune. I think the close coupling to large metal earth threw things off. Operating outside was pleasant and signals were very good.
The Moorabbin & District Radio Club Hamfest must be one of the biggest in Victoria and it's always a good excuse to pick up some parts and catch up with friends.
My feeling was that it was a bit smaller than last year but still worth a visit. I purchased a Bird power meter with a fault (but it came with the needed part). A few pushbuttons and a vintage morse key being sold from an SK estate by Drew. A few impressions of the show:
The in-line power/SWR meter I bought was said to be faulty due to a burnt out diode. The Seller supplied me with a replacement and said he hadn't got around to fixing it.
When I got it home, I opened it up and tested both diodes and they seem to be OK. Attaching a transmitter and it seems to work. I'm not too concerned about calibration so I'm happy with the purchase. It came with 2x N to BNC adapters which are probably worth what I paid for the whole thing.
I headed off early to visit VK3ZZC who's unwell at the moment. We wish him all the best for a speedy recovery. Great to catch up with Drew VK3XU, Peter VK3YPG, Nigel VK3DZ, Dave VK3ASE, Peter VK3YE, Chris VK3AML, Jim VK3ZKK, and others.
How long until it takes over our lives or jobs completely?
Also self-driving trucks on the road and we bid farewell to Skype.
Peter Marks, a software developer and technology commentator from Access Informatics, joined Philip Clark on Nightlife to discuss the latest news in technology.
https://www.abc.net.au/listen/programs/nightlife/nightlife-tech-talk-with-peter-marks/105261180
The Macedon Ranges Amateur Radio Club had a table with information for potential new members.
ALARA, WIA and many others had tables and there was quite a bit of gear for sale at excellent prices.
I presented a talk on how AI is being used in the new versions of FreeDV.
Congratulations to the organisers and I hope they do it again.
An early electronics project for me was to construct an RF noise bridge. This remarkably simple device, combined with a receiver, let me measure resistive and reactive impedance by adjusting for a null in the noise on the receiver.
I'm putting together a compact station for portable operation and it occurred to me that a noise bridge might be a good way to adjust an antenna tuner used to match an end fed wire in a tree. Sometimes it's hard to find the resonant point.
I tried this with a random wire, a Z match and a QMX transceiver (with the recent SSB software). It was not a good way to tune up, partly because of the QMX's excellent AGC.
To see what's going on I hooked up an SDR as the receiver, so I can see the noise over a broad bandwidth:
The antenna is an off centre fed dipole and the tuner is a simple L match. The dip can be seen above up the top end of 40m after tuning. A traditional antenna analyser confirms the tuning:
So it does work but is difficult compared to other options such as minimising an LED on the Z-match or using a NanoVNA.
I wonder if I'm not doing this correctly. I'm not seeing what I would characterise as a "deep null".
The Palomar bridge is a nice bit of gear and I rather like the warning on the back of the manual:
They have an article about using the noise bridge for antenna tuning. Oh, and this story is another example of Betteridge's law of headlines.
Sample code for rotary encoder handling that I've found seems to double step with my encoder. I guess there's other that have half steps or something. Anyhow, here's how I've been doing it and it's working just fine.
So, the interrupt triggers just on the falling edge of the clock pin and then looks to see if the data pin is high (for clockwise) or low (counter-clockwise).
A full project is stored here.
Recently, I've been enjoying developing embedded projects on an RP2040 zero board using MicroPython. The RP2040s are fast and cheap and the zero board is much more compact than the Pi Pico but has more than enough I/O for my needs. (Actually, all the I/O is there if you need it).
MicroPython is a wonderful language and I like the fact that the source code is on the device so I can always find it again.
The normal way to develop MicroPython is Thonny. It's fine but the editor is rudimentary compared the modern code editors with completion and AI suggestions.
Recently I've discovered the MicroPico extension for VSCode and it is working pretty well.
The environment does all the things I need including showing the files on the board, letting me run the current file, stop it, and use the REPL console.
Most impressive is the AI code completion which often stuns me with its guesses about what I was about to type. (The suggestion is the italic stuff after time. below).
MicroPico doesn't do the firmware install but that's quite easy on the RP2040 (hold the boot button and plug in).
The files stored on the device are shown in the "Mpy Remote Workspace" area on the left and a project folder is above. You can drag files up or down between areas but it moves the file. To copy a file on macOS you option-drag as is the normal convention here.
I wish single step debugging was available for MicroPython but if I'm debugging pure python algorithmic code it can be debugged locally if needed.
There are other MicroPython extensions for VSCode but this one seems to work quite well for me.
As part of my objective to take the SolderSmoke DC receiver forward to be a double sideband transceiver I've been messing about with an Si5351 based VFO. The CPU is an RP2040 Zero board which I program in Micropython. I've just bought a couple of these handy boards that include a 1.3 inch OLED display, a rotary encoder and two extra push buttons.
No documentation comes with it but the edge pins are nicely labeled on the back.
When I hooked it up and tried my existing code, written for an SSD1306 OLED, the display showed mostly noise. It turns out the boards with a larger, 1.3 inch, display require the SH1106 driver which I found here. Both drivers subclass the Micropython Framebuffer class which is a very interesting thing in its own right.
The display / encoder board has nice big mounting holes on the corners as you can see.
I paid AU$6.79 each for the larger display version on AliExpress. For you in America I guess they'll be about $100. ;-) The board seems to be widely available and is called "0.96/1.3-inch OLED Display Module With Button EC11 Rotary Encoder IIC Interface LCD Screen"
I've seen an OSError stack trace when trying to talk to an I2C device on the wrong address and wondered what EIO means. It would be nice to have a list of all the error codes and what they mean.
From what I've read, error numbers are different for each hardware port of MicroPython. I'm using a Raspberry PI PICO and can get a list like this:
An interesting discussion of Digital Radio Mondiale. Some comments about how the west has retreated from Shortwave broadcasting are particularly pertinent at the moment.
It turns out that quite a few of my fellow members of the Macedon Ranges Amateur Radio Club are also members of the Old Timers.
There's a good train service from central Victoria down to Melbourne and then on to the Caulfield RSL where we meet so, naturally, we ended up on the train together. Here is VK3MO, VK3ACR, VK3XW, VK3WQ and VK3RV. Also in attendance was VK3CCR.
The meeting was well attended and the food was very good.
The Radio Old Timers Club is a national organisation but to my knowledge only Melbourne and Perth have lunch events.
Graeme, VK3CDO, came and gave a great presentation about portable operations gear at the Macedon Ranges Amateur Radio Club recently. He brought along a terrific folding chair and table which I immediately ordered. He suggested an outing and I was up for it. We set up on a beautiful day here in Victoria on Mount Macedon.
The weather was perfect. We both brought our chairs and tables. I brought a tent in case the weather turned (not likely). Graeme used a very nice MA-12 vertical antenna which was easy to set up and worked well. I strung up an end fed but had problems tuning it to either 40 or 20m. (I think the Unun I grabbed was not working).
Graeme operated a low cost, uSDX QRP radio with just the internal battery and easily made a contact.
We both brought small metho stoves which worked very well for cups of coffee & tea. Later we each cooked up a lunch. Graeme went for gourmet sausages while I tried a freeze dried meal which was very nice.
Graeme put me on to the chair and table. Both excellent: "Naturehike Camping Chair, Portable Backpacking Breathable Chair with Storage Bag, Compact Collapsible Lightweight Camp Chair (Green-M)" & "Naturehike Camping Detachable Table with Aluminum Alloy Material, Portable, Lightweight, Outdoor Furniture for Camping, Picnic, Hiking, and Other Outdoor Activities".
The tent is a "Night Cat Backpacking Tent fo 1 Person 2 Persons Easy Setup by Clip Waterproof Lightweight protable Camping Hiking Tent for Adults Kids Scouts Tent". I like it because it's under 2kg and has a convenient side entrance.
I kept John “lofty” Wiseman’s excellent SAS survival handbook at hand but luckily there were no emergencies requiring reference to it.
I look forward to even more ambitious outings in the future.
