I want to point out that what keeps this 'OK' is that the little wire is so 'electrically short' compared to the actual wavelength at 1000khz (a real quarter wave antenna at that freq is like 75 meters)... and thus this limits the power of this 'transmitter' to probably nanowatts.
If the PIO pin could drive a fair amount of current at 3.3v into a long enough wire at that frequency you'd start to get into milliwatts, and AM radio is NOT a band that even amateur license operators can broadcast over a a certain power on. FCC part 15 dictates no more than a 3 meter antenna for personal devices at AM frequencies which is what does the power limiting essentially.
The harmonics fall off quick enough on such a setup that it wouldn't really be a problem - but the only way to really KNOW that is to have a real solid understanding of how this 'radio' you've just made is working, meaning how that square carrier wave is really being driven off the PIO pin, and thus you need the requisite EE knowledge and/or ham radio test equipment and experience.
I've seen more and more of these 'ChatGPT coded up a radio transmitter' posts and it kinda rubs me the wrong way. I'd like to see more calculations and disclaimers for people showing some responsibility with radio, and if it drives people to studying and taking an amateur radio license test that would be for the better...
At least you are supposed to be allowed to transmit on AM (and FM) bands at very low power, at least under FCC rules. That's how they can sell those adapters for car radios. Some other ones you definitely are not supposed to use as far as I know, like the old analog TV signals - I've seen a couple of those sorts of projects recently. On the other hand, you can go and buy an illegal TV transmitter on Amazon right now.
Also a reasonably even bet that you already own a low-quality wall power supply that will produce more interference than anything you're going to be doing with a Pico and a 4" jumper wire (I've found a couple of offending devices in my house), but I'm certainly in no position to tell you if you should or shouldn't do something.
Without the proper knowledge or measurement equipment, I observed that the audio would fade out after a 30 cm distance. Combined with running it for mere seconds to test and record a demo, I assumed to be in the clear with the spirit of the regulations. Appreciate the reminder to be responsible with RF.
If you're interested in this I definitely recommend you look into amateur radio licensing. I took mine a few years ago simply out of interest, and I learned so much from the advanced course.
VHF and UFH are so deeply embedded in technology we almost forget it's there. It's fun to sweep for other peoples environmental sensors in your neighbourhood, even more fun to track and listen to satellites as they pass overhead.
I don’t know what the regulations are in your country (looks like you are maybe in Canada?), but in many countries it is straightforward to get an amateur radio license, and then you can have all sorts of fun (under the rules).
Transmitting on AM broadcast frequencies is generally prohibited unless it meets an extremely low-power exemption , even if you have amateur license(I have a Japanese amateur radio license). A practical way to reduce risk is to put a large resistor before the antenna so the radiated power stays within that exemption. You could start with 100 MΩ; if the receiver cannot pick it up, try 10 MΩ, and so on.
There's still one example of a working offshore radio ship, the Ross Revenge in southern England which you can go and visit. She's one of the former Radio Caroline ships, the studios are still fired up every month for a weekend of broadcasting and they run tours. Radio Caroline themselves are still alive and kicking as a legal station broadcasting 24/7 online and on 648 AM; ironically the latter transmission comes from a former BBC World Service site. She wasn't really a 'pirate radio' ship as she was a Panamanian-flagged vessel in international waters so not subject to the Wireless Telegraphy Act in theory, but British citizens specifically would have committed an offence working on her in her free radio days. What really did Radio Caroline in as an offshore broadcaster was the Anglo-Dutch action against the clandestine organisation which supplied the ship, that and the move from a 3-mile to a 12-mile limit which forced her into more exposed waters.
Other than the RNI ship she was probably the best-equipped radio ship that ever put to sea, and certainly the strongest. She was a long-range trawler built for Arctic conditions, and the engineering which went into the radio station was really impressive; Peter Chicago her engineer by all rights should be up there with the greats in hacker lore. Most radio ships were clapped-out old vessels at the end of their lives, they were essentially slapped with transmitters and sent to sea to die since you can never take a radio ship back into port once it's broadcast. The Ross Revenge on the other hand was a very strong ship who was left purposeless midway through her life due to the Cod Wars. The generating and transmitting facilities were really sophisticated for radio pirates, there were plenty of redundancies and the ship could radiate multiple medium and short wave services.
The broadcast studios and accommodation are still active but most of the machinery spaces and the hull itself aren't in good condition. They've raised half a million pounds for repairs, but that's not actually all that much in the maritime conservation game. Hopefully it will be enough to stabilise the immediate problems with the hull and open a door to lottery funding though. If you're in the area I'd go and see her while you've definitely got the chance!
I fly between various countries in western Europe a dozen times a year and have done so for a decade and every single time I've boarded a plane I have had to shown a photo ID with my name on it that matches my name on the plane ticket. Most of the time the gate agent barely looks at the ID/name, but it is required to hand it to them. I have never once just walked on a plane without showing ID with my name on it, and I have never seen anyone in line in front of me do so, ever, and I'm talking hundreds of flights at this point. It doesn't have to be a passport, I see older Spanish people showing their driver's license only all the time, but it has to have a photo and a name (to match the name on the ticket in some way) and be a state issued ID. Again, they seem very lenient with that whole name matching thing and checking the authenticity of the ID (it isn't scanned, just visually inspected), but I've never seen anyone just say 'no' and get on a plane.
So what the hell part of the EU are you talking about where they don't ask for any ID at the point where you are boarding, whatsoever?
For reference, here is Iberia's page for required ID when flying, and I've seen that this is absolutely enforced every time when checking in and boarding.
I live in a late 18th-century rowhouse where there is large stonework for window sills/surrounds/doorways all done in a very specific pink granite that was carved from a shoreline quarry a significant distance away. Massive stones, 100kg+ each, had to be transported by horse-drawn cart, over not-easy-terrain, a distance that would have taken two horses probably 8-9 hours per trip, and enough stones that it was probably 15-20 trips. Let alone the effort that had to have been required to carve surprisingly square/cuboid shapes from solid granite without power tools. It's mindblowing to me that someone was able to afford such a home construction, let alone the time taken to do it, in ~ 1790. It isn't a particularly rare style in this neighborhood either.
Fast forward 200 years, and I was sweating at the cost just to hire someone to deliver new hardwood countertops from a place not much further away. By truck. By a single person. In a single afternoon. No horses required.
Are you anywhere near (the remains of?) a canal network? That was how bulk cargo was generally transported in the 18th century. First-mile + last-mile would be by wagon, of course, though usually pulled by oxen, not horses. Canals were economically revolutionary, for 100-150 years, until railroads largely supplanted them. They remained viable, in limited circumstances (ie, some routes for some cargos), until the mid-20th century.
Astute observation; no canal, but there is a river outflow to a bay, whereby a ship could have carried stones from the quarry, albeit a long way around a peninsula; it is possible that was a more effective way to get them close, and then use horse and cart to get them the last bit of distance.
Thinking about the logistics of such a feat at that time is wild to me for just the construction of a private residence.
Whenever I see press on these new 'rack scale' systems, the first thing I think is something along the lines of: "man I hope the BIOS and OS's and whatnot supporting these racks are relatively robust and documented/open sourced enough so that 40 years from now when you can buy an entire rack system for $500, some kid in a garage will be able to boot and run code on these".
Depends on the residence. I have personally seen a large house in Brooklyn with dual 200 amp 120/208 volt three phase services (two meters, each feeding a panel.) I have seen someone setup an old SGI rack scale Origin 3000 systems in their garage. I think they even had an electrician upgrade their service to accommodate it.
100% this. But don't forget the garden hose running full blast so you can cool it! It's not impossible to get up and running for fun for an hour, but this isn't a run 24/7 kinda setup any more than getting an old mainframe running in one's garage is practical.
The firmware is UEFI and Vera should have good upstream support. The GPU driver is proprietary though, so you'll have to dig up the last supported version from 2036.
I'd wager they will use what is known as a 'Float-on/float-off' ship for transport... it's rather common actually-
It's a ship with a very low deck line that partially submerges itself, with the center of the deck underwater deep enough so the other vessel can 'float on' over the deck. They they pump the water back out, raising the deck above water and the boat on top it just rests flat.
Given the reputation for the cost and provenance of the cameras I'm surprised that Hasselblad passed through QC with that solder spooge at the edge that got into the frame of the film. I mean... it's visible on all the photos. I'm surprised that someone didn't notice that in testing before the camera left and send it back. Hell, even if I bought a cheap camera today and every photo has a little unexposed notch in the edge I'd be pissed. If you told me a camera was going to the moon I'd think I'd want the frame to be flawless....
The table lists F1 cars as having "Carbon fiber brake calipers".
This is glaringly incorrect. All current brake calipers are machined from aluminum, specifically Aluminum-Lithium or Aluminum-Copper alloys. There is a rule denoting bulk elasticity modulus limit on brake calipers of 80 GPa, which was set just at that to allow the more exotic Lithium Aluminum alloys but to dis-allow Titanium alloys or anything else stiffer (There was experimentation with Titanium calipers in the past.)
Absolutely no calipers are made from composites, CF, graphite, or otherwise.
Discs are Carbon-carbon.
So you're telling me that simply walking out to the car and hitting a button inside the car is just too much of an "inconvenient experience"?
You know we used to have to drive the car... sometimes many miles... to a station, get out, and fill it up with a liquid fuel that costs many times more, and then drive home...
Seriously now- The perceived 'inconvenience' you have is the reason that so many of these connected features are being pushed and then the because the ability is there the business types can't resist the data gathering that became possible because of all the antennas, etc.
Yes, because it's entirely possible to do. Hell, the manufacturer even charged a price when you bought the car, or I can pay the $20 for my lifetime share of server usage.
If the PIO pin could drive a fair amount of current at 3.3v into a long enough wire at that frequency you'd start to get into milliwatts, and AM radio is NOT a band that even amateur license operators can broadcast over a a certain power on. FCC part 15 dictates no more than a 3 meter antenna for personal devices at AM frequencies which is what does the power limiting essentially.
The harmonics fall off quick enough on such a setup that it wouldn't really be a problem - but the only way to really KNOW that is to have a real solid understanding of how this 'radio' you've just made is working, meaning how that square carrier wave is really being driven off the PIO pin, and thus you need the requisite EE knowledge and/or ham radio test equipment and experience.
I've seen more and more of these 'ChatGPT coded up a radio transmitter' posts and it kinda rubs me the wrong way. I'd like to see more calculations and disclaimers for people showing some responsibility with radio, and if it drives people to studying and taking an amateur radio license test that would be for the better...
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