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> Having said that, even as a hobbyist, I don't see what's wrong with it? Maybe I have written some code that is already running on my Arduino, and I want to add a sensor that is only available for RPi, without having to hop onto another platform... nothing wrong with that.

...use a piece of wire ? None of the interfaces are fast enough to need a breakout board.

It's not "all arduino to rPi hats" adapters either (which would be far more useful tbh), it's "that special expensive ARM stick from arduino to rPi hats".


Soo its adapter to make small board that is more expensive and slower than rPi... bigger ?

What exactly is the selling point of that ?


allows you to reuse pi accessories on your arduino. seems like a good selling point to me?


This isn't "an arduino." It's merely made by Arduino.

This thing is an i.mx8 SoC running some shitty arduino distro, combined with an STM32. It has nothing in common with the arduino boards most people typically use.


Not at arduino prices


Hobbyist and beginners who are bored.


> The excessive restrictions harm more boring usage like "I want to check my email from the woods on infrastructure that I built and maintain". The larpy usage doesn't care, because it's mostly fantasy and if there were some doomsday event no one is going to care what encryption you're using (or at least won't be able to do anything about it). :)

Amateur radio bands are not intended to work as ghetto ISP bands.

Whether there should be some lowers band available for that is another discussion.


That position is inconsistent with both the law and the history of amateur radio. There is no general field of use restrictions (outside of music and broadcast which themselves were originally allowed but eventually restricted to restrict competition for commercial broadcasters). Amateur radio is open to qualified persons of any age who are interested in radio technique solely with a personal aim and without pecuniary interest.


There was also never expectation of privacy of communication. You can send your emails thru amateur radio in plaintext just fine


You can't because (among other reasons) the responses may contain naughty words-- you can't even read HN or most amateur radio forums over amateur radio without violating the regulations. You also cannot use standard software over the radio due to the mandatory encryption (or inability to do authentication without encryption) which is ubiquitious in software designed for use on public networks.


All the time. Fiat 126p ("Maluch") was famously known for being as safe as Mercedes ("in both of them crumple zone ends at engine") and being as sporty and advanced as Porsche ("both have engine in the boot")


Well, petrol or diesel isn't that nice either


Anhydrous ammonia is much worse, creating rolling clouds of ground level deadly gas for long distances. And being very flammable. And explosive.

Gas doing 2 of those 3, and diesel only 1.


I agree, it's kind of a different class of threat for everyday people.

Not assuming it would be the same, but picturing a spill at a gas station. Spilling gas is a problem, but at least it's just sort of there. If you get an ammonia leak and it forms a vapor cloud, I don't think most people would know how to deal with that. I'll bet your spilled gas likely won't migrate into the intersection.

But on the plus side, we already see what handling/transportation of large amounts looks like for agriculture, even if rail carriers etc. dislike dealing with it.


For sure - definitely doable, and certainly not the worst industrial chemical used at large scale. But not super consumer friendly.


Correction: Ammonia is not flammable since the flash point is significantly above room temperature. It would only be explosive if you consider the pressure vessel exploding, but we also have natural gas powered cars which also have pressurized cylinders. The main real issue is the toxicity.


Nope. Anhydrous ammonia between 18-25% is literally ‘explodes like gas vapor’ type explosive/flammable.

[https://www.worksafebc.com/en/resources/health-safety/risk-a....] [https://www.osha.gov/laws-regs/standardinterpretations/1994-....]

It does have a higher ignition point than gas. But one a spark can definitely reach. It’s been a common problem in industry where ammonia gets used a lot (refrigeration in particular).

BLEVE’s are also a problem too of course. And the toxic nature of breathing it in! Haha.


Wasn’t that what happened on the docks in Beirut? Or were their fireworks stored next to it that time


Different (but related) chemical. That was ammonium nitrate (fertilizer + blasting agent). Which ammonia is used to make at large scale.


The flash point is well above any ambient temperature it would be stored at.


Your point is?

Gasoline fumes don’t typically auto-ignite either. And that is all flash point is about.


No, autoignition and flash point are two completely different things.


Ah, thanks for the correction.

Anhydrous ammonia’s ‘flash point’ (producing flammable/explosive vapors) is well below room temperature at STP? It boils at -28F. That’s why it is so commonly used for refrigeration.

It does have a specific LEL and UEL that makes it less dangerous than gasoline. It also has a much higher auto ignition temp.

Yeah, anhydrous ammonia is less dangerous than gasoline (1 instead of 4) on the fire diamond due to it being less easy to ignite.

But flash point doesn’t help you here?

electrical sparks or open flame can still definitely do it. And have, multiple times.

Some pretty amazing clips in industrial accident videos from it, actually. My favorite part is when the chunk of roof almost makes it to the highway.

[https://youtu.be/QWCiqoLb-VU?si=ZEsBDFVTQkHSpkRS]


Flash point and boiling points are different. The flashpoint of ammonia is 270F. Below this temperature at 1 atm, ammonia will not catch fire no matter what.

That video took place in an engine room, so any combination of heat, flame, or spark is possible.


“Flash point is the temperature a liquid (usually a petroleum product) will form a vapour in the air near its surface that will “flash,” or briefly ignite, on exposure to an open flame”

If ammonia is boiling (and producing a fog) of concentrated vapor which then burns/explodes in exposure to an open flame, which it will definitely do at even OF, that is an entirely academic point no?

It still has the same effect.


Who cares of it explodes, just breathing the stuff is deadly.


If it is cheap, that will beat out a lot of other concerns. Not sufficient for consumer use, but power plants are already hazardous places that can engineer significant safety controls.


Could we use this process as a building block in the synthesis of some "nicer" fuel? What can ammonia be semi-efficiently converted to?

Edit: Maybe methanol?


Well... there's hydrazine (N2H4) which is the stuff they use as monopropellant rocket fuel. It burns even without the presence of oxygen and it's even more toxic and explosive than ammonia. It's the reason the capture crews for returning spacecrafts wear hazmat suits.

However hydrazine is liquid at room temperature and it can be converted to hydrazone (also being considered for fuel cells) which is solid at room temperature and non-reactive... until it comes into contact with water at which point it all turns back into hydrazine.

But yeah no there's really not a "nicer" fuel. Generally, if it has nitrogen in it and it isn't literally just nitrogen with itself, it's dangerous. And the more nitrogens it has the more dangerous it is.


If there is anything that would make ammonia seem warm and cuddly, it is indeed hydrazine!

Urea maybe? It’s almost non toxic and is 2x ammonia + a carbon monoxide molecule.

though not sure how efficient it would be to extract energy from.

Speaking of ‘extra nitrogen’s are generally bad’, a callout to the azides!

https://en.m.wikipedia.org/wiki/Azide

https://en.m.wikipedia.org/wiki/Lead(II)_azide


P.S. Found a sweet Hydrazine youtube video, and figured I needed to add it. [https://youtu.be/V3HuKQvRBUE?si=wTuEwvKJQkidKZAp]


Diesel is none of those things.

I have extinguished a fire with diesel.


Diesel is definitely flammable. I works great as an accelerant.

It isn’t as easily flammable as gas, and doesn’t have easily autoignitable vapor like gas.

I’m guessing you dumped a lot of it on something without a lot of thermal mass?

If you did the same on a bonfire, you’d have a different story.


Diesel's flash point is above ambient temperature (unless you live in the Sahara). It has a lower autoignition point than gasoline, which is one of the reasons it's preferred in compression ignition engines.


I’m not sure what you’re trying to say here?

If you dump gasoline on a fire, it will go ‘fwoomp’ and try to climb back into whatever container you poured it out of. If it succeeds, that container may even explode. Which is bad, and why people die or get terrible burns from pouring gasoline on fires.

If you pour diesel on a fire, the fire will get bigger and none of those things will happen. Unless, apparently, like the poster above, you pour so much on it so fast it drowns it before the diesel can get up to temp. Apparently. I’ve personally never tried that.

Diesel is basically cooking oil in many ways, and you can do the same thing with cooking oil too if you want.

This is well known by every redneck I’ve ever met, and I’ve personally done it numerous times.

P.S. also, putting gasoline on cold fuel in warm climates makes a pretty cool fireball due to said flashpoint. Just, you know, don’t light it from close up. Cold climates? No problem.


Well the idea is stupid and makes no sense but

> How is this any easier or more effective than just having a website that hosts its own advertising assets

advertisers REALLY don't want you to do that because it's far too easy to cheat.


> advertisers REALLY don't want you to do that because it's far too easy to cheat.

I expect that they are already cheating as much as possible to convince their customers to continue paying for advertising that has a negligible effect on the bottom line.

Adtech and PR firms would have you believe that it is impossible to sell a product or service online without first paying them $10k/m. It's also why google search is so awful - if they could get you the information you were looking for they are sidelining their customers, so their search has to, by design, be limited so that their customers are more prominent in the search results than non-customers.

Note: I'm not saying that this is by design; they could get to this stable equilibrium simply by each isolated team within search, advertising, etc aggressively pursuing its own metrics.


Well they can't have it both ways. They can either play wackamole with consumers or their customers.


App still needs to be written to be scalable. And if shit hits the fan moving to cloud (...or just renting dedicated servers at 1/3 the cloud cost) isn't too bad


I feel like a lot of that shifted now.

You can just have on-premise k8s and keep most of the velocity gained from developers being able to "just run stuff" instead of anything having to go thru sysadmins.

You can just rent few servers off OVH to start and not have to worry about actual hardware, while still being few times cheaper than cloud.

Yeah you won't have access to the slew of cloud services and will have to deploy your own database but with amount of readily available code and software to do it it doesn't really slow down experimenting all that much


> You can just have on-premise k8s

You can deploy bare k8s, but then you'd figure that you need a lot more, starting with a load balancer (luckily there is MetalLB).

It's all possible, but not simple.


It's insane between actually renting servers, or even classical "bare" VPS providers and cloud too.


Renting dedicated server off company like OVH, or even co-locating your own is also far cheaper than cloud, few times over, without fuss of turning your house into datacenter.


There is a time cost, but most of it is a one off, and not that difficult, and there are tools to make it easier.


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