Wednesday, October 07, 2026
Simple JTTY app for Linux
Tech Talk on ABC Radio - what computer skills do we need in the future
AI is changing all of that with being 'user friendly' the whole AI schtick!
Philip Clark is joined by Peter Marks, software developer and technology commentator from Access Informatics, with a look at what skills we will now need into the future.
https://www.abc.net.au/listen/programs/nightlife/what-computer-skills-do-we-need-for-our-future/107235742
Tuesday, October 06, 2026
JTTY - new mode for keyboard short message chat on HF
At the time of writing it's not quite out yet but it's in the release candidate of WSJT-X 3.2 so it won't be long.
Stephen, VK2BLQ, drew my attention to it and we had a chat between Melbourne and Sydney (714km {for Americans, sorry, I don't know how many football fields that is}).
We both reduced power to 1W and were able to talk without any problem.
Leaving it running on 40m I can see quite a bit of activity (click the image at left to see more).
It's great to have modes that work without the need for second accurate time synchronisation as this open the door to portable operation without internet.
Recently I've also been playing with RattleGram which is a similar idea of short messages over radio. There are apps for Android and iOS. It seems to be mostly used on VHF/UHF FM radios and probably isn't ideal for HF conditions.
I do miss the days of PSK31 when I used to have fascinating long form text contacts.
Saturday, October 03, 2026
Phase nulling direction finder for fox hunting
Our club is holding a fox hunt in a few months. We have a few portable UHF beam antennas but I thought I'd try a simple design that uses the phase difference between two sense antennas. It's called a HANDI-Finder and was described in QST in 1993.
It uses a CD4047 oscillator divider to make a nice square wave and two diodes to mix the incoming signals. In my case the oscillator is at around 600Hz. When the phase is equal no tone is heard, otherwise you hear the tone in a receiver tuned to the frequency you're hunting. Here's the board:
To try it out I used a NanoVNA to generate a CW signal. Here's a demo:
It's available as a kit but they kindly make the circuit easy to find here. See https://handi-finder.com/ for full information.
Wednesday, September 30, 2026
Cleaned the work bench - why is it so damn hard?
My electronics work bench seems to descend in to entropy of its own accord faster than I can deal with it. Part of the problem is my short attention span - I start new projects before finishing the current ones.
I've had "clean shack bench" on my daily Reminder list, haunting me for months. Finally, over two days, I've taken drastic action.
Part of the problem is all those components, plugs, sockets, adapters, and bits of wire fall between not useful enough to have a proper box to go in and not useless enough to go in the bin.
My radio shack is quite small - probably a good thing - like a gas, junk expands to fill the available volume.
Cleaning up also triggers the mind and it's hard not to see something and start tinkering with it again.
Anyhow, I'm pleased that it looks good enough to work on again.
Tuesday, September 29, 2026
Built another NE602/LM386 Direct Conversion Receiver
In recent months I've been off in the land of software development and have been sadly ignoring the electronics workbench. To get me back in the mood I built another instance of the simple direct conversion receiver using two ICs described in Experimental Methods in RF Design.
NE602 mixer chips are a bit hard to find and the only ones I have are surface mount so you can see it on a little carrier board above. This design uses the on-chip oscillator. My tuning is extremely sensitive and will need some padding to give me band spread of just the 40m band. At this point I haven't tuned the front end and it's undoubtably way off so the receiver is quite deaf.
In the past I've built the, all discrete component, Soldersmoke Direct Conversion Receiver. That project is much more challenging than this little one but each has it's good ideas. I'm thinking of bringing over the PTO from Soldersmoke to this design just for fun (or perhaps over-thinking it and adding an Si5351 VFO!).
Here's the schematic.
(Click to enlarge).
Wednesday, September 23, 2026
Tech Talk on ABC Radio - AI dangers and opportunities
Prime Minister Anthony Albanese in the US talking AI at the United Nations, and Nightlife looks at where this technology is heading and what it could mean for all of us.
Peter Marks, software developer and technology commentator from Access Informatics, joined Philip Clark and listeners to Nightlife with the latest tech news and information. You can listen here.
Tuesday, September 22, 2026
Some terrific club events
I've been a bit quiet here on the blog recently, in part due to some excellent club events I've been involved with.
The Macedon Ranges Amateur Radio Club had a great meeting with two fascinating talks.
Beekeeping Meets Radio: Building a LoRa Network for the Apiary
Bouncing Light Off Clouds: 357 km Across Bass Strait on 730 nm
The Radio Amateurs Old Timers Club had:
Melbourne ATV Repeater VK3RTV A Brief History – the journey from Analogue AM to High Definition Television by Peter Cossins, VK3BFG.
We are lucky to have so many excellent speakers and events here in Victoria, Australia.
Friday, September 11, 2026
My longest distance FreeDV RADEV1 contact 14,342km
There have been reports recently of 20m openings so I left WSPR receiving and noticed the US was coming in. Switched over to FreeDV RADEV1 using my macOS version of the software called FreeDVNeo. Keyed down and on Reporter I could see that Dudley WA5QPZ in Austin Texas was receiving me. Not perfect copy, but not bad either.
Also, I'm running the release candidate of macOS 27 Golden Gate which will be out in a few days. So far it seems stable and fast.
Thursday, September 10, 2026
Robert Glasser - my 97.5 year old uncle, friend and radio amateur has died
It's a credit to his kids, my cousins, Tracey and Paul, that Robert was able to stay at his home (with visiting carers) until just about the end. I know he appreciated that very much.
I would visit every few months when in Melbourne to catch up with friends and he was always excited to see me and hear about the evolution of ham radio technology. Once I dropped in on the way back from the Rosebud Radiofest and gave him a copy of the 1956 ARRL Handbook. He leafed through it and exclaimed "nothing's changed!".
On another visit I brought along an IC-705 and showed him the waterfall display. He was impressed.
In later years he had a 2m radio but rarely was on air.
Robert, and his wife my dear aunt Peggy (who was an amazing person in her own right and the subject of this ABC program), were always kind and encouraging to me as a child and rather lost teenager.
I asked Robert about his ham radio history during a visit in 2025.
Robert got his amateur licence when he was seventeen. You had to have morse code which he had known from childhood. The morse test “wasn’t too much of a problem for me”. 15 words per minute. People would buy tapes, punch tapes, to learn the code.
Callsign was W6HWA “Hard working American”
An early transceiver he owned was a Hallicrafters SR-150. He may have had a Collins KWM-1.
He had a three element beam for 20, 40 and 80m.
At Albany road he had a tilt-over tower with a beam that did 20 and 10m.
At seventeen, Robert lived in California.
Robert had contacts both locally and overseas. Mostly just calling CQ rather than regular nets.
I showed Robert a QMX transceiver. He was amazed at the size and the fact that it did multiple bands including 80m.
We discussed the difficulty of soldering to enamelled wire used to wind toroids.
We discussed QST magazine and the ARRL.
Robert moved to Australia in 1950. He rattled off a series of addresses in California where he had lived.
We discussed WSPR beaconing and low power operation. There had been a large solar flare in the last few days.
Robert commented “how times have changed!”.
Henry Radio was a shop he used.
Robert asked if the ham radio license is easy to get these days. We discussed the levels and the fact that tests are now multiple choice rather than essay.
“A lot of water has gone under the bridge”.
Robert’s dad was a real estate broker in California. Mainly houses. Beverly Hills. Beachside communities.
I mentioned the Palisades where there have been fires. Robert said he lived there at one point but got out in time.
Robert’s older brother had married a girl from Melbourne and he came out to visit his brother. His brother was nine years older. He introduced Robert to Peg who he used to produce on radio. Robert just stayed in Australia after that. He can’t even recall going home for a visit (but he must have).
“Time marches on, we’re all getting older.”
Farewell dear Robert. I will always remember you. Ex W6HWA , VK3QA & VK3DRG SK.
Wednesday, September 09, 2026
Tech Talk on ABC - with Cat Marks
It might be seen as nepotism except for the fact that she's much more qualified and certainly smarter than me. Here's her spot:
The UK has just taken its first step into the Robotaxi era, with Wayve's self-driving cars now available to book through the Uber app; but there'll still be a licensed human driver in the front to take over if needed.
Communications Minister Anika Wells has announced that the draft Digital Duty of Care law will be introduced into parliament this week, including a requirement that platforms offer the ability to 'opt-out' of their algorithms. What does this all mean?
Cat Marks, data scientist and Principal at Ember Advisors, joined Philip Clark and listeners to Nightlife with all the latest in tech news. Listen here: https://www.abc.net.au/listen/programs/nightlife/nightlife-tech-cat-marks/107131014
Tuesday, September 08, 2026
USB-C Power on Airbus
On the trip north to the recent walk I was lucky enough to fly on a couple of different recent Airbus planes in the Qantas fleet. The last one was an A220 which has this USB power port on the seat back:
Having bought, and tested, a few Chinese chargers, I'm a bit sceptical of the Watt claims on USB-C ports but I'm happy to report that Airbus is telling the truth. The macOS WhatCable tool is very handy.
Yep, 20V at 3A = 60W. Great stuff.
The internet connection on the A220 tested at 18Mbps which is fine for general use. The plane I caught up to Sydney last week was a brand new Airbus A321-XLR and the internet speed was outstanding:
Malcolm Turnbul wouldn't need this speed but I thought it was great to see it.
Yuraygir coastal walk
Along the way are stunning beaches, charming bush tracks, and a bit of rather challenging rock scrambles. To mix things up there's a couple of river crossings, two of which required boats to pick us up.
You really can't do this without support and in our case the trip was supported and guided by Marcus from Home Comforts Hiking.
Walking south is certainly the best way to do it. We had the sun, and usually the wind at our backs.
I'd just left Drummond, Victoria, where it was 10C and I'd had the fire heating the house and arrived where it was 30C for much of the walk.
Happily I did not suffer from any blisters or other mishaps and felt faily fit probably due to my daily bush walks at home. Having said that, my feet were a bit sore at the end of each day but recovered by the morning.
Our guide Marcus did a wonderful job and the logistics all worked well bar a coffee shop that didn't open as advertised for breakfast one morning.
Wednesday, August 26, 2026
Tech talk on ABC - Google preferred sources, the X algorithm, and cutting the price of hearing aids
Could choosing your trusted news sources help support journalism in the age of AI summaries and algorithmic feeds?
Also, a new study published in the Proceedings of the National Academy of Sciences titled “Value misalignment of X’s feed algorithm” found, unsurprisingly, that the site’s algorithm prioritised engagement above all else when it generates a users “For You Page”.
What’s been revealed is that rather than simply showing more of what we agree with, the algorithm is deliberately mis-aligned in that it shows us things they know we don’t agree with so that we are prompted to comment on it, often angrily.
Finally, in the US, the Food and Drug Administration (FDA) regulates hearing aids and last week they approved Samsung Galaxy Earbuds under a category of “over the counter” hearing aids.
This follows a similar decision in 2024 about Apple AirPods Pro. Having the two biggest manufacturers of smartphones able to sell hearing aids at a fraction of the price of prescription products: $400 rather than $4,000 is a major win for people with milder types of hearing loss.
You can listen here: https://www.abc.net.au/listen/programs/nightlife/nightlife-tech-talk-with-peter-marks/107077464
Thursday, August 20, 2026
Vale Hansen Yee
Beloved next door neighbour Hansen Yee aged just 82 has died.
Hansen was charming, modest and clearly intelligent. He was Associate Professor of Electrical Engineering at Sydney University. Aparrently a brilliant student.
After his wife Cora died, he joined us for Xmas dinners and was a lovely part of our children's lives. He tutored daughter Cat in Maths.
Vale Dr Hansen Yee BSc BE PhD, MIEEE.
Monday, August 17, 2026
CYD Ham Dashboard
The "Cheap Yellow Display" boards are a low cost board with an ESP32, a colour touch screen and a bunch of other useful I/O. I've long used them to display my solar stats (generating, using, net). I just noticed this excellent project HenrysCat esp32-cyd-ham-dashboard. There's an excellent web flash tool which works well.
It can roll through seven screens (you can turn some off if you wish). Here's a few:
The web flash tool shows this. I used the first option.
But my screen came up mirrored so I tried the second. In that case the screen was blank white so I went back to the first. When it boots up it creates a Wifi network with a captive portal. I found that the setting default to mirrored - which seems like a poor choice.
It's a great gadget to stick up in the shack. Great work to HenrysCat and claude. Source code here.
Thursday, August 13, 2026
MacBook Air 11 - still great after all these years
I hand down my old laptops and phones to the kids who happily use them for years. Sometimes I try to hand down an update and are met with resistance - this (old) one still works fine, why should I change? When they do, they're stunned by the performance improvement. They are still going through the Intel to Apple Silicon transition.
Recently I got an 11-inch, Mid 2013, MacBook air back, and decided to get it going. The battery was completely dead. I paid $45 for a battery on AliExpress. They are easy to install on the 11 inch Airs and the battery came with the two screwdrivers needed.
There was quite a lot of dust and fluff to remove but the fan still moves well. My daughter got very good use out of this machine. It has a few dents in the edge but the screen is good and all the keys work. (I've done a lot of cleaning with a cotton bud but more to do). What's striking is that she's typed so much on it that the most used keycaps have worn the labels off them.
Even with "just" 4GB of RAM, the machine is surprisingly usable for email and web surfing. But being stuck on macOS 11 means that there are many apps that won't run and lots of sites complain about the version of Safari.
Some apps, like my beloved BBEdit, still keep old versions available.
I love the compact size of these and the fact that I could replace it for under $200 if the need arose means that this would be a good laptop to take somewhere where it might be stolen or damaged without too much anxiety.
Apple should make a new compact laptop. I love my modern Air but would be very attracted to something smaller for my messenger bag.
Pain points of running macOS 11
- BBEdit 15.1.4 https://www.barebones.com/support/bbedit/updates.html#up151
- Obsidian 1.10.6 https://github.com/obsidianmd/obsidian-releases/releases#release-v1.10.6
- NetNewswire 5.0.4 https://netnewswire.com/old-versions.html
- Chrome 138 https://google-chrome.en.uptodown.com/mac/download/1095647884
Wednesday, August 12, 2026
Tech Talk on ABC - Is AI killing the goose that laid the golden egg?
Many sites that create content - be it news or analysis - are funded either by advertising or subscription. The reduction in traffic threatens their business model.
Peter Marks, software developer and technology commentator from Access Informatics, joined Philip Clark and listeners to Nightlife with the latest tech news and information. Listen here and read Sue Ahearn's piece here.
Tuesday, August 11, 2026
Great interview with home brewer Paul VK3HN
Paul is an inspiring QRP home brewer. Great interview on a recent podcast. https://youtu.be/Rkd1o2PQI9M?si=gzKmEFHAueIDsdYK
Recommended.
Sunday, August 09, 2026
Single step debug on a PICO
As you might guess, I'm really getting in to using the Raspberry Pi PICO for embedded development. If I can do a job in MicroPython I will but the C/C++ tools and the library they provide is a fantastic step up from the Arduino. The official plugin for Visual Studio Code is really excellent. I purchased the official debug probe and it seems excellent.
You can compile and run with a single button but more interestingly you can single step debug and look at variables.
Claude code is a real help and just for fun I asked it to make a program that makes the PICO emulate a USB audio output device feeding the audio to a PWM DAC pin which I've added a simple low pass filter to.
It sounds great:
The debug probe makes it easy to install and run new builds. You don't need to unplug and plug while holding the Boot button, you just click the run debug button. Interestingly it loads the ELF binary rather than the UF2 binary that you'd drag to the mounted volume.
My interest in being a USB audio device stems from my interest in making an embedded version of at least bits of FreeDV RADE.
The PICO 2 is quite a powerhouse although doesn't have enough RAM for what I have in mind. I haver some 3rd party boards on the way with extra RAM so we shall see.
Saturday, August 08, 2026
Running ML on a Pico
Before the days of FreeDV RADE (which uses multiple machine learning models to turn speech to features, transmit data over HF, and turn the demodulated features back in to speech audio; it was possible to run FreeDV with Codec2 on embedded hardware.
There was the SM1000 and the EzDV boxes.
I wondered if it might be possible to divide up the tasks and perhaps use several microcontrollers working together. I would not have attempted this before the days of AI tools like Claude Code but last night decided to give it a whirl.
This project captures audio from a MEMS PDM microphone. PDM is pulse density modulation and these little microphones have excellent sound.
LPCNet is the input side of the FARGAN vocoder. It turns speech audio into "features" which are a stream of 32bit floating point numbers. In FreeDV RADE, these features are transmitted over the air with an ML modem (but that's another story). The recovered features are turned back into speech audio with the Vocoder.
This project live encodes the audio to a stream of features which it sends over a USB serial cable to a computer which has a python program which syncs up and captures the features to a file which can be decoded using one of the test tools with FreeDV.
Here's me talking in to it followed by a decode of the features captured.
I tried to get this going on a PICO but it could not keep up. Partly because it doesn't have floating point and must emulate it. The PICO2 keeps up and even has some head room. There is some work down sampling the audio from the microphone that could be dropped if I used an A/D input instead.
Now here is a features to speech decode side. Features are streamed over USB. Audio is PWM into a simple low pass filter. (My tests indicate that this can sound very good). So far the audio is understandable but quite poor.
I'm not sure that the Radio Autoencoder can fit on one of these but you never know... Any recommendations of easy to use embedded ARM boards?
I'll share the code when it's a bit more polished. Not sure that this will be of interest to anyone but you never know.
Wednesday, August 05, 2026
Sunday, August 02, 2026
AI tools causing an improvement in software quality
I just saw the announcement of NetBSD 11. Software that has been around for many years. What struck me was this comment:
As you are probably aware, the number of security issues found or suspected everywhere has massively increased with the advent of AI tools. As a consequence, we can't publish a release without open issues. Instead of delaying the release further to fix them (new ones are being reported all the time), we've instead chosen to be transparent about this.
NetBSD is not alone, recently we've seen:
- Record AI Bug Fixes Push Google To Twice-Weekly Chrome Updates
- Microsoft ships largest Patch Tuesday on record and Microsoft Patches Record 622 Flaws, Including Two Zero-Days Under Active Attack
- Oracle Releases Record 1,449 Security Patches As Companies Face Patch Overload
- AI has become Apple’s latest bug detective
FreeDV Sunday net
Nice net this morning with VK2, VK3, VK4 stations participating. A few new stations which is always good to hear.
Again I ran the net using my macOS client FreeDVNeo. On the frequency were VK5FD, VK5RA, VK5AG, VK5ABE, VK3KEZ, VK3JCO, VK3GTP, VK2KNC, VK2BLQ, VK2AOO, VK3ZTR, VK2LUI (no activity though), VK3PT (first time caller), VK3FAR, VK2KNC, VK5JPL and me VK3TPM.
See you next Sunday from 09:30 eastern time normally on 7.197 but +- depending on band usage.
Wednesday, July 29, 2026
Tech Talk on ABC Radio - ALP conference resolution on AI
We also discus AI models that hack and "sleepers" - a problem facing robotaxi firms. Listen here: https://www.abc.net.au/listen/programs/nightlife/nightlife-tech-talk-with-peter-marks/106968258
Wednesday, July 22, 2026
Upgraded the SSD in an M4 Mac Mini
When I purchased my M4 Mac Mini I chose 512GB of SSD thinking that would be more than enough. (I'm old enough to remember running on a 200MB disk). Developer tools and video editing eats a lot of space and I ran out. I had already paid an extra A$300 to get 512GB, to go from the default of 256GB up to 1TB Apple charges A$750, so I decided to attempt a cheaper option, and puchased a new 1TB SSD from AliExpress for A$375.
There are plenty of videos showing how to pop the bottom off the computer and get to the SSD.
The board came with a spludger and a screw driver with the required bits. I was careful with the cable to the power button and fan. Unlike some upgraders I did not remove the power button and all was well.
Once the new, blank, drive is installed you need to put the machine in to DFU mode by holding the power button while plugging in the mains power. The power light blinks orange.
Next step is to plug the middle USB-C socket to another mac which detects DFU and offers to repair or restore the "faulty" mac. As this is a new drive choose Restore.
This is where I had problems. For some reason my internet has occasional ping fails and the downloading of the software image would fail.
The error message isn't terribly helpful as you can see here.
In the end I located the restore image and downloaded it manually. The trick is to Option-Click the Restore button which lets you choose the restore image. This worked.
The disk seems fast and I have enough space. For now, I would say, 1TB seems to be needed for developers. AI models are also huge and I expect will be eating many people's hard disks in the next few years.
Enphase solar monitor on ESP32 CYD
A MicroPython project that turns a CYD (Cheap Yellow Display) — an ESP32 board with an integrated 320×240 ILI9341 TFT — into a live dashboard for a home solar system. It polls an Enphase Envoy gateway on the local network and displays current generation, consumption, and net power, along with a scrolling line graph of recent history.
Along the way I ran in to a problem with HTTPS from MicroPython on ESP32 that turned out to be a known bug. To get it to work I've had to use an older version of MicroPython for ESP32.
You'll need to log in to your Enphase account and generate a token which lasts a year.
The code is here on GitHub.
Monday, July 20, 2026
Toyota Yaris - won't start "Drive Start control malfunction" - easy fix
My wife hasn't driven her Toyota Yaris hybrid for some weeks and today when she tried to start it was shown a series of alarming errors.
Happily as well as indicating a serious problem with the car, these can also be a side effect of a low accessory battery. I opened the bonnet but there's no battery I could see. Turns out the fuse box has a special place for jump starting.
I charged at 8A for only a few minutes and the car started just fine. We took it for a drive.
FreeDV Sunday net - good turnout VK3, VK2, VK5
Another good FreeDV RADEV1 net on Sunday. My macOS client was acting up so I used the official client this week.
As is often the case there were comments about audio quality. Charlie, VK3ZD, had particularly crisp audio and it turned out that he had cut the bass and boosted treble in the app. I tried the same here but reports came in of clipping so care is needed.
Stations on the net were VK2BLQ, VK2DWG, VK2KNC, VK3FAR, VK3FC, VK3GTP, VK3JCO, VK3KEZ, VK3UBK, VK3ZD, VK3ZTR, VK5ABE, VK5AG, VK5RA and me VK3TPM.












































