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I'm really impressed by Ingenuity

https://en.wikipedia.org/wiki/Ingenuity_(helicopter)

It was sent to Mars with a plan for 5 flights and a total of 7 or 8 minutes flight time. It ended up flying for over 2 hours in 72 seperate flights before it damaged itself with a bad landing. Not quite the "this thing is still doing science almost 50 years later" that Voyager can claim, but impressively engineered so it lasted way beyond it's initial mission plan.


> I don't think "slingshot" is the right analogy here.

I think it's perfect - a very valid "David vs Goliath" reference.


Note that it is wrong to think that David was at a disadvantage. I know that is not how the story is taught today, but slingshot troops of that age we the snipers of their age: very deadly (not at the range of a modern sniper, but...).

If the fight between them was started at some distance, the David should have been the expected winner by pretty much everyone on the field. Think "bright a club to a gun fight" sort of vibes.


David had a sling, not a slingshot. They are very different tools. slings need more skill, but are easy for a shepard to learn. (I suspect more powerful as well but I'm not an expert)

Ah, I hadn't thought of that sort of slingshot! I was thinking more "primitive rock throwing."

There is also a cost aspect of it as well.

The long range drones that are being shot down are the "expensive products" of a military industrial complex.

The US solution to this problem is even more expensive.

For the cost the Ukraine's solution might as well be a rock: https://en.wikipedia.org/wiki/Sting_(drone)


Stock dark pattern verbiage...

I'm a little surprised the options aren't "Enable" and "Ask me later".


If you could get that 100,000Amps flowing through your speaker wire, the vaporised copper and the plasma channel would probably keep your 100MW flowing, at least until your building caught fire.

Even your monster cable? ;)

Well, it'd still vaporise, but it'd sound smoother and more musical as it did it, and the soundstage from the plasma arc would be _stunning!_

It's almost worth the experiment and your cables are a sacrifice I'm willing to make. For science, of course.

You're _so_ right!

I'm pretty sure you have my delivery address from when I bought sorted Lego from you about 10 years back.

Let me know when to expect the 100,000Amp test equipment!

I shall make sure I wear better PPE than just my reading glasses.

:-)


This would be the funniest thing to do. 100K Amps is doable, the question is for how long. That would be one very impressive bank of capacitors. And to turn a 00 into plasma would have some spectacular side effects, such as raining molten copper across a sizeable area. Just your reading glasses would indeed not be enough, there probably isn't any PPE that I would consider entirely safe other than sufficient distance from ground zero. But now I'm really curious. I have a spot welder that will do bursts of 5KA and that will happily throw the breaker every so many welds. 100KA sustained will be a fair engineering challenge.

Ah, that lego project... that was one I always wondered if I should have industrialized it but sourcing enough lego was a real problem.



Holy crap. That's a whole series of bad ideas extremely well executed. That guy probably has never seen what a lead acid battery can do when it explodes. He keeps hiding away from the hot metal but in the path of ~half of those batteries. Ignorance is bliss.

That's low voltage lightning :)


He was gifted an arch flash suit by the guys from Lightening on Demand :D

"The gift of life". Complete madness.

See also (as posted elsethread): https://www.youtube.com/watch?v=RoGbrgOhPes

> I realized I may be talking to a serious audiophile, didn't mean to disrespect your Monster cables.

I am a recovering audiophool.

I do own a pair of 2m long Monster Cable speaker cables (with locking gold plated banana plugs). I am fairly certain I've used welders with smaller cables.

(In my defence, I bought those as a teenager in the late 80s. I am not so easily marketed to with snake oil these days. I hope.)

(On the other hand, I really like the idea of a reliably stable plus and minus 70V or maybe 100V DC power supply to my house. That'd make audio power amplifiers much easier and lighter...)


I think there'a a regulatory "Low Voltage" definition of "below 50V", which has implications around whether you need to be a licensed electrician to install it or not. Anything above that is - for at least some purposes - considered "High Voltage".

Other people, of course, have other definitions of high voltage:

"This resonant tower is known as a Tesla coil. This particular one is just over 17 feet tall and it can generate about a million volts at 60,000 cycles per second."

and:

"This pulse forming network can deliver a shaped pulse of over 50,000 amps with a total energy of about 1,057 times the tower primary energy"

https://www.youtube.com/watch?v=RoGbrgOhPes


That's traded off against the increase efficiency of LED lighting, at least compared to incandescent lighting. An LED "equivalent replacement" for a typical incandescent globe is down around 1/10th of the power. A 7Watt LED bulb is typically marketed as "60W equivalent". If that configured as a bunch of LEDs in series (or series/parallel) that need 12VDC, it's right about the same current draw as the 120V 60W incandescent equivalent. (Or perhaps double the current for those of us who get 220VAC out of our walls.)

(Am I just showing my age here? How many of you have ever bought incandescent globes for house lighting? I vaguely recall it may be illegal to sell them here in .au these days. I really like quartz halogen globes, and use them in 4 or 5 desk lamps I have, but these days I need to get globes for em out of China instead of being able to pick them up from the supermarket like I could 10 or 20 years ago.)


Heh - I vaporised a fairly large soldering iron tip (probably 4mm copper cylindrical bar?), when I fucked up soldering a connector to a big 7 cell ~6000mAHr LiPo battery and shorted the terminals. Quite how I didn't end up blind or in hospital I don't know. It reinforced just how much respect you need to pay to even low-ish voltage DC when the available current was likely able to exceed 700A by a fair margin momentarily. I think those cells were rated at 60C continuous and 120C for 5 seconds.

heh man, I'm glad you got out of that easy, I definitely wore safety glasses 100% of the time after my experience. I think a lifetime of experience with dangerous wall outlets and harmless little 1.5V/9V DC cells teaches us the wrong lessons about DC safety. I've since heard stories of wrenches exploding when they fall across EV high voltage battery terminals. Wrenches aren't supposed to be explosive.

The electricians I was working with also told me stories about how with the really big breakers, you don't stand in front of it when you throw it, because sometimes it can turn into a cloud of molten metal vapor. And that's just using them as intended.


A bunch of those big breakers require two people. One person in a flash suit and another with a 2m long pole around the first person. That way if an arc flash happens, the second person can yank the first person to safety without also getting hurt.

Why don't they use the pole to flip the breaker from 2m away?

Ruins the fun and interrupts instilling respect deep into the bones of interns.

Allegedly

While on "work experience" from high school I was put on washing power lines coming straight out of the local power station near the ocean - lots of salt buildups to clear.

Same deal, flashover suits and occasional arcs .. and much laughter from the ground operators who drifted the work bucket close.


Amps - the old 48vdc telco data centers vaporized wrenchs once in a while.

Those harmless 9V DC cells can do a lot of damage if you use them right.

This reminds me of the sailor who [decided](https://darwinawards.com/darwin/darwin1999-50.html) to measure his internal resistance by pushing probes through the skin on his thumbs and electrocuted himself with the 9V multimeter battery.

Mythbusters time. Salty fluids can be remarkably conductive. Blood qualifies. What's interesting though is that you have to wonder if there isn't some contributing factor here, as a kid I did this quite a few times, so that's one more for that list of stuff that could have killed me. At the same time: I didn't have nice insulation piercing tips back then (I do now) and that may be what saved me. I will definitely not try this again.

Another story in the same line is that I heard that a horse got killed by contact with a lantern battery, but I don't have any reference for that, just a story by a family member that collected coaches.


You got super lucky.

Yep. Super super lucky. I suspect my reading glasses are the only reason I can still see anything.

I have a couple of those narrow escapes one of which led me to put a significant chunk of Eastern Amsterdam out of power. Another involved Beryllium oxide. 9 lives are barely enough.

Ah! Perhaps you are a member of the gigawatt club? Eligible for entry once you have accidentally tripped off 1000 MW of load or generation! No sweeping that under the table

You brought back a memory, a second hand one, but still a great story. A guy I knew long ago had emigrated from NZ to NL. His main claim to fame in NZ was that one day he showed up drunk for work. In itself this wouldn't have been memorable, if it wasn't for his job, which was to manage a relatively small hydro plant on one of three shifts. On that particular day the plant had to be brought back online after being out for service and since it was really old the synchronization was manual. You had to control the flow of the water, monitor two concentric spinning wheels with the one driven by the grid and the other driven by the local genny and when the phase markings were lined up 'just so' you had to engage this frankenstein level switch to couple the grid to the generator and from there on inertia did it's thing so you could open up the gate to allow more water so the generator would start leading the grid effectively generating power.

Any kid could do it. Probably. But not a drunk one and instead of waiting long enough for both wheels to stay synchronized indicating there would be only a small jump in phase he just said f* it and connected the two anyway. Predictably, this led to a serious disturbance to the grid which in turn caused a whole lot of other stuff to disengage. Since his chances for re-employment on account of his new-found fame were somewhat minimal he decided to emigrate instead :)


I'm the idiot that sent a fairly high voltage spike into the grid setting off a cascade. Even years later I do not fully understand how it could happen, you'd think the grid would be low impedance enough to absorb a spike like that. But it set off a cascade on a part of the local grid that was known to be weak.

Somehow I simultaneously desperately want to be in that club, and never want to be responsible for an event that would let me join that club...

I would read that book...

'Stupid stuff I've done and survived'...

Sure, maybe?

If your house gets 800V DC you're still gonna need "bricks" to convert that to 5VDC of 12VDC (or maybe 19VDC) that most of the things that currently have "bricks" need.

And if your house gets lower voltage DC, you're gonna have the problem of worth-stealing sized wiring to run your stove, water heater, or car charger.

I reckon it'd be nice to have USB C PD ports everywhere I have a 220VAC power point, but 5 years ago that'd have been a USB type A port - and even now those'd be getting close to useless. We use a Type I (AS/NZS 2112) power point plug here - and that hasn't needed to change in probably a century. I doubt there's ever been a low voltage DC plug/socket standard that's lasted in use for anything like that long - probably the old "car cigarette lighter" 12DC thing? I'm glad I don't have a house full of those.


"So God created mankind in his own image"

I wonder if that made it into the training set intentionally, or just as an unexpected side effect of stealing every character of text available on the internet with absolutely no curation?


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