A recent podcast from Freakonomics titled Why do your Eyeglasses cost $1,000? explains the EssilorLuxottica monopoly we face here in Australia as well as the US. Their markups are described by one analyst as "obscene". They mention Warby Parker as a possible monopoly breaker but sadly they don't seem to have come to Australia.
My prescription is relatively complex with astigmatism and I've paid $800 for progressive lenses and $300 for computer distance reading glasses.
Despite efforts by eye testers I've been able to get a copy of my prescription and recently ordered some new reading glasses from Zenottic in China for $55 (plus $10 shipping). They are perfect and the frames seem as good as any in the local shops.
I think it's a scandal that we pay 5 times the price, or more, to buy locally. It does take some care to get the prescription down correctly as well as inter-ocular distance but once I got it right I'm able to cheaply get additional pairs.
Note that EssilorLuxottica owns Sunglass Hut, OPSM, Oakley, Ray-Ban, LensCrafters and many more.
This week on ABC Radio Nightlife, we talked about Samsung's product updates and how much they look like Apple products, a new way to migrate your photos from Google to Apple's cloud, future cars that won't let you speed, Android's coming desktop mode, some old technology (8 inch floppy disks) that are finally being retired and the US ban on Kaspersky Anti-Virus. Listen here.
Our home came with a Saxon wood heater but the advertised automatic fan control circuit has never worked and I must get down on the floor to turn the fan on or off manually.
The heater works by heating a cement plate at the top of the firebox and a fan runs air over the top of it which warms the room. If the fan isn't on the heat goes up the flu. If the fan is on when the fire isn't going well it cools the firebox and may extinguish the fire.
I enquired at the company about getting this fixed or getting a replacement board and they referred me to our local agent who basically said they knew nothing.
The circuit certainly looks quite simple although the markings on the IC have been cleaned off.
My solution was to purchase a temperature controller XH-W3001 that can be used either in heating mode or cooling mode. I've set it to come on when the sensor is over 30C indicating that the fire is hot inside.
The sensor range is only up to 120C so I've put the sensor at the back above the heater. The XH-W3001 was AU$5.98 which seems very reasonable. The mains wires are rather flimsy but should be OK for switching a fan.
The way it works is a little counter-intuitive. It has a "heating mode" and a "cooling mode". I'm using it in cooling mode where the output comes on when the temperature exceeds the left hand value and goes off when the temperature drops below the right hand value.
I've set left to 34C and right to 30C. The sensor is at the back just poked in to the top cavity. It seems to be working well and the cat is very impressed.
My new eBike came with a charger. Even though it's about 10m away from my ham shack the radiated noise level is impressive.
Here's the "transmitter":
Here's the inside view:
Even with external clip-on ferrites on the mains and output cable there is little difference. How can it be legal to sell noise makers like this? Are all the certifications fake or just incredibly poor standards?
As Ralph, VK3ZZC, suggested I have added 0.1uF silver mica capacitors across the large electrolytic smoothing capacitors on the output and this has made a noticable improvement on the radio.
I joined Philip Clark on ABC Radio's Nightlife program to talk about technology news including new legislation to combat faked sender IDs on scam text messages, YouTube live stream hacks to promote crypto scams and a look at the new ARM based Microsoft Surface laptops that are challenging Apple.
In the story I talked about trying out the new Microsoft Surface laptop powered by ARM. It's a nice looking and feeling laptop, quite similar to the M2 MacBook Air which I imagine it is competing with. Fit and finish is excellent. More ports than Apple and slightly better value in terms of price per GB of storage and RAM.
There's a new Microsoft only key on the right hand side for summoning Copilot AI features.
I pushed the key and not a lot seemed to happen but I guess, like Apple these new features are being rolled out over time.
This little post was triggered by reading Owen Duffy's post titled "Arduino thermometer using DS18B20 and OLED display". Even though I'm quite comfortable writing C or C++, I've been enjoying the clean MicroPython environment. These days I've pretty much switched from classic Atmel Arduinos to RP2040 based boards.
I implemented this little thermometer in just a few minutes with two easy to find and install libraries. Here's how it looks:
Obviously adjust for the pins you've used. The RP2040 is a wonderfully powerful chip. The board I used here is from Seeed studio.
Cheers to Owen for all his great insights and sharing.
ChatGPT is very good at Micropython
While I'm here, an observation about the utility of the Large Language Models. I have been asking ChatGPT to write code to demonstrate how to do things and it's really good!
Around the house I have little devices that use Wifi to poll my solar inverter and show power use and generation. I've been using a third party JSON parser but I asked ChatGPT how to do it and it mentioned a built-in JSON parser that I wasn't aware of!
When I was a teenager and just starting to tinker with electronics I built a regenerative receiver kit from the local Tandy (RadioShack) store. It was a great success and I was able to listen to the big shortwave broadcasters on it.
Most of the components I had but the ten turn pot had to be ordered in. I used a T50-2 toroid core rather than the air-core inductors. At first it didn't oscillate. My initial thought was that the tickler coil was not the right polarity but it turned out that my 2N2222s have collector and emitter reversed. Ralph, VK3ZZC, suggested that they might be fakes but the gain seemed fine.
The coil has a single turn that can be connected to a frequency counter. I have it going to my CRO and it's helpful for reading frequency and seeing when regeneration is starting. While you can, kind of, listen to single sideband, AM is best. Here's a bit from 7125 this morning.
I didn't have any 1N4001s in stock and tried another power rectifier that didn't seem to work as a varicap diode. I did have a genuine varicap in the junk box but it was too sensitive. Richard, VK3LRJ, gave me some 1N4004s and they work fine although tuning is very sensitive.
The radio is pretty hard to operate and one must juggle, RF gain, tuning and regeneration.
My memory might be rosy but the Tandy pegboard kit was easier to use than this design. It might be this one. There's a lot more electrical noise around these days and many of the big shortwave broadcasters have gone so perhaps the golden age of listening to BBC on a three transistor radio are over.
Some years ago I used to accompany Terry to a field in Sydney where he would fly amazingly fast while using a video headset. He would run through an obstacle course with hoops standing on the oval. I tried a few times but crashed immediately - I could never put myself in the drone and was always thinking of the sound.
My current drone is home built and rather bashed about but does the job.
One problem I've had is that I need my glasses to see the screen clearly and the solution was to sacrifice an old pair of reading glasses and apply some hot glue.
There is a bit of open space and a tree in the middle so I started slowly and have had a bit of a breakthrough. I was able to take off, fly around the tree, and return and land without breaking anything.
A few days on and I've probably had about ten successful flights and it is a real joy to experience.
Last night, after a hard landing, the drone was not flying well and I lost control. I couldn't see when it was but could see the video from its point of view. It was stuck in a tree. A squid pole was very handy in dislodging it. Next step is to add a buzzer so I can locate it after an uncontrolled landing.
Tuned to 9585KHz and the BBC's Antarctic Midwinter Broadcast is on. A charming shortwave program with information and messages from family at home. Good signal here in Victoria.
I'm using an Airspy HF+ via SDR++ in server mode. Thanks to Stephen, VK2BLQ for the tip.
Talked technology on ABC Nightlife with Dom Knight: AI seems to be taking jobs already, AI being used to protect call centre workers, NotebookLM a great new research tool and Adobe being sued for misleading customers.
USB-C is a wonderful standard. Apart from the ability to plug it in either way up, it supports Power Delivery and much higher speeds. I've run in to some mystifying scenarios where a cable would charge but not carry data, would carry data but not charge, and lower than expected data throughput.
I'm a registered Apple developer and was keen to try out the macOS 15 Sequoia beta but I'm not an idiot so decided to install it on an external disk on my Mac mini.
The steps were:
Used Disk Utility to format a Samsung T5 drive as APFS
Downloaded the Sonoma macOS installer via the App Store
Installed Sonoma macOS 14 on the external drive
Booted from the external drive and enabled Beta Updates in the Software Update settings and chose macOS 14
When all that was done I booted from the external drive.
Sequoia seems quite stable and I've been able to build my applications with the Xcode beta.
But.... it did seem rather slow! I used the Blackmagic disk speed test to measure the drive and got Write: 38.9 MB/s & Read: 39.3 MB/s.
The USB3.1 port is capable of 10Gb/s or 1,250MB/s so something is up.
Changing USB-C cables to one marked as 10Gbp/s I re-measured and got Write: 263.6MB/s & Read: 344.9MB/s. Almost 10x improvement but well short of what's possible.
Today, I bought a 1TB Western Digital drive. Blackmagic gave me Write: 804.1 MB/s & Read: 906.8 MB/s.
The Mac mini has two Thunderbolt/USB4 ports that are capable of up to 40Gb/s so I have ordered a Thunderbolt enclosure.
Oh, and just a note that the speed of the internal SSD on a mac is pretty amazing. Blackmagic measures the internal SSD as Write: 3049.6 MB/s & Read: 2856.4 MB/s. I guess that's why I noticed the slow speed.
Summary: If things seems slow, try another USB-C cable. (I wish they had a standard for markings on the cables with their capabilities).
Update: faster external disk
Wanting to get closer to the speed my interfaces are capable of I ordered an NVMe SSD stick and case from AliExpress. Plugged in to the USB-C socket on the back of the Mac mini I get the same speed plugged in to the USB-C hub outlets on my monitor so I'm using that. Speed is pretty good. Close to 1GB/s.
The enclosures are pretty nice. Mine came with a heatsink, sticky pad and even the screwdriver needed to open it. Not as small or neat as the Samsung T5 but five times faster.
Update 2: even faster external disk
On my quest for a faster external drive to boot from I ordered a SanDisk Professional drive and plugged it in to the USB-C socket on the back of the Mac mini. At 2,677 MB/s this is getting pretty close to the internal drive speed.
I've been seeing a lot of misinformation lately and noticing the techniques used. While discussing this with friend Tony, I wondered if ChatGPT could list ten effective ways to do this.
"Spreading misinformation effectively, while unethical and harmful, often employs psychological and social manipulation. Here are ten techniques commonly used:
1. Emotional Appeals: Crafting messages that trigger strong emotions, such as fear, anger, or joy, can bypass critical thinking and make the information more memorable and persuasive.
2. Repetition: Repeating a false statement frequently can make it more familiar, leading people to believe it's true (the "illusory truth effect").
3. Selective Presentation: Sharing only specific facts or stories that support the misinformation while omitting contradictory evidence creates a biased view.
4. False Authority: Citing fake experts or misrepresenting the credentials of individuals can give false information an air of credibility.
5. Echo Chambers: Sharing misinformation within closed or like-minded groups reinforces the false beliefs, as members are less likely to encounter opposing views.
6. Manipulated Content: Using doctored images, videos, or audio clips to create convincing but fake evidence supporting the misinformation.
7. Bots and Trolls: Deploying automated accounts and paid individuals to amplify misinformation across social media platforms, making it seem more widely accepted.
8. Headline Manipulation: Crafting sensational, misleading, or clickbait headlines that can spread quickly even if the actual content is less inflammatory.
9. Conspiracy Theories: Developing complex narratives that explain events through secret plots, which can be compelling and difficult to disprove.
10. Astroturfing: Creating the illusion of widespread grassroots support or opposition through fake reviews, comments, or social media activity.
These methods exploit cognitive biases, emotional responses, and the structure of information dissemination in the digital age to spread and entrench misinformation."
I wonder if some sort of score-card could be made that analyses a published story in terms of these factors?
It's a pity the Raspberry Pi PICO comes with the horrible micro USB socket. I purchased what, I guess, is a PI Pico clone board with a USB-C socket on it from AliExpress but was disappointed when none of them seemed to appear on the USB bus.
On a whim, I plugged one in to my computer with a USB-A to C cable and up it came! My guess is that somehow the USB-C wiring isn't right and a proper USB-C port doesn't power on. Anyhow, they work fine and I've now flashed MicroPython v1.23 on to them and all works well.
My thanks to Stephen Rapley, VK2RH, for passing on this review of ham radio software that gave my WSPR Watch app a high rating.
It's in the latest June issue of German amateur radio magazine FUNK amateur.
Translating the text with Google Translate I get:
"Who can hear me? Where can I be heard? Who can I receive? These questions can be answered with the WSPRwatch app. Your own reception reports and those of other stations can be displayed in a list, on a map, Figure 1, or as a graphical evaluation. However, the information does not only come from WSPRnet, as the name suggests. Timebase DB, Reverse Beacon Network and PSK Reporter can also be selected as data sources.
Users have a wide range of setting and filtering options at their disposal.
The data can be exported in CSV format for other applications.
Linking the app to your own QRZ.com account adds further information to the spots displayed, such as the name and exact location of the call sign owner."
Stephen added "You appear at the top of a list of apps ranked by “Nutzerbewertung”! (User ratings)."
Had a nice chat with the brilliant Dom Knight about technology news including Ticketek, Windows Recall, Face recognition failures, Google AI summaries, "filmmaker" mode on TVs and what to expect from Apple's developer conference next week.
I've been working on the acoustics in my home studio. It was a bit of an echo chamber so this week I hung a blanket from the ceiling behind me and it seems to work nicely.
I don't normally post links but this story caught my attention and deserves more coverage.
It's not that long ago that I bought some test tubes from a place on Harris Street, Ultimo, Sydney. They had a scientific glass blower working at the time.
This morning I saw that the (very active) Bendigo Amateur Radio and Electronics Club were transmitting RTTY on 7.035. When I'm not in the shack I often leave an AirSpy HF+ running connected to SDR++ in server mode. This means I can sit by the fire and tune around on HF.
To decode a digital mode audio must be fed to FlDigi. I use BlackHole for routing audio from one app to another but I wanted to hear the audio as well so needed a way to send audio from the SDR++ app to both my speakers and a loopback for FlDigi.
The trick on macOS is in the Audio Midi Setup app. Create a new "Multi-Output Device" and set the outputs to both BlackHole and your normal audio output (I use headphones with speakers plugged in to them.
The audio output in the SDR software is set to send to the Multi-Output Device.
FlDigi is set to get input audio from BlackHole.
The final result is audio I can hear but also decode in FlDigi. Here's a bit of the BAREC broadcast.
Thanks BAREC for running the digital broadcast. I think it's great to have some regular signals on the band that aren't just FT8.
There is a nifty little PCB based end fed antenna Unun and winder being sold in the Chinese stores online. It does look a lot like the ones sold by QRPGuys. The kit comes with the BNC socket, a capacitor, a toroid, some cable ties, the butterfly nut and bold, and a length of enamelled copper wire. It doesn't come with the antenna wire.
I cut the wire for a 20m band antenna. The flatness of the SWR curve suggests rather high losses in the toroid.
For a 20m band antenna there is enough space to wind the wire around it but I think it wouldn't be enough for lower bands.
Strung up near the house it certainly brings in CW and FT8 signals well on 20m.
The capacitor doesn't look like a high voltage type and I wouldn't want to transmit more than a very few watts into this. I could substitute the capacitor and toroid. It's very compact and something to throw in the travel bag but I wouldn't trust this for extended digital transmission.
During my recent frustration with the Telstra supplied NBN fixed wireless I ordered Starlink. This morning the box arrived. More compact than I had anticipated.
The "out of box" experience is excellent, I would say it matches Apple's standard.
I put the "dish" (really a small flat panel) on the roof facing south and powered it up.
The app contacted a satellite and then asked me to rotate it 9 degrees. Within minutes it was working and speed is better than any internet I've ever had.
That Speedtest is run on a Wifi connected Mac. The Starlink app's Speedtest is faster but I assume testing at the router rather than what you really get.
Not bad. I'm amazed at the ping latency given that I'm using a satellite internet service.
There's a small obstruction which I'm hoping to eliminate by moving the panel. It might even be the ladder which is propped up near the antenna.
I've cancelled my Telstra / NBN service who, incidentally, just wrote to increase the price. Starlink is a bit more expensive per month and I had to pay AU$600 for the gear. It's certainly better value per bandwidth and their customer support seems much better. I like the honesty of showing outages proactively.
If you have a good view of the sky it's worth considering.
An outage!
On 29-May it looked like a software update was being pushed out but later, reading the Reddit Starlink forum revealed a global outage of up to 20 minutes for some people.
The honesty about outages, even ones I don't notice, is refreshing after the secrecy of Telstra and NBN.
Things are back to normal and download speed is amazing at times:
I read that outages like this one are rare.
Wind resistance
It's been quite windy recently and I was concerned that the little "dish" would move out of alignment or even get blown off the roof. So far, no movement as shown in the alignment tool in the app.
The alignment tool is excellent. I didn't realise at first that it is a live view so when I'm up on the roof I can push the dish around and see it move in the app in real time. Wind hasn't been a problem so far but as a slight help I've added a house brick.
Mesh router
Although I have ethernet between the sheds here I have had a little trouble with the link not coming up at 1Gbps so I ordered a Starlink mesh router. Very simple setup and seems to work well. Interestingly these mesh routers are well prepared for water resistance. I guess people mount them outside.
I do miss the control over my network that is in the GL.inet routers I was using - things like assigning static IP addresses. I tried putting the Starlink router into bypass mode but for some reason my router didn't get an IP address so I've put that project aside for the time being. I really hope Starlink ads some more advanced features to their router in the future.
Power draw
An off-grid friend asked how much power the Starlink v4 uses. I hooked a power meter up to the mains and as you'll see from this video, it's about 50W and the total for 24 hours is 1.2KWhrs.
There's no snow here normally so I don't think the melt heater will operate but obviously that will increase power load if used.
Where I live, in country Victoria, internet is via NBN fixed wireless. I pay AU$100 a month for unlimited. Signal strength was not full bars and would sometimes drop in rain - probably because the signal path goes through trees. Speeds were about 20-30Mbps download and that was enough for streaming video and video calls.
A few months ago, there was some sort of upgrade and speed jumped to over 50Mbps download. I was very pleased.
About a week ago there were three days of disruption due to an NBN "upgrade". At the end of that period, signal strength had dropped and speed was down to sometimes 2Mbps.
I tried the normal things, turning off the NBN box for periods of time and back on again, hoping it would re-sync or something. We have a Facebook group for local residents and I posted there asking if other people were seeing the same thing. Two others said yes so presumably there are others as well. A few of us reported a fault via our providers. I'm with Telstra so started the process via the chat.
Note that they don't make it easy to report a problem and, I guess correctly, they said the connection was working.
The support people clearly use a script and even though I listed all the steps taken so far they seem oblivious of this and asked me again.
There are frustrating terminology issues. They asked about the "modem" and I thought they meant the NBN fixed wireless modem but in fact they meant the Telstra Wifi router.
It's strange that they have no visibility of other customers having issues and NBN rarely seems to be aware of any problems. Surely a network operator has monitoring in place?
After several hours doing things including plugging a laptop in to the NBN device via an Ethernet cable they agreed there was a problem and escalated to NBN. A technician was booked to visit my house in four days time. Another local said she had an appointment on Tuesday. You might think they'd visit all properties at the same time.
In the end all of our visit appointments were cancelled and magically the signal strength is now better than ever and bandwidth looks better than ever.
However, during the outage period I decided to order Starlink. The gear should arrive within the next few days and I'm fascinated to try it out. I have some concern about obstruction from some tall trees.
It's great to have another option.
Update
Amusingly Telstra just emailed to say the price is going up.
