CanadaPlus

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[–] CanadaPlus@lemmy.sdf.org 2 points 8 hours ago* (last edited 8 hours ago)

Disclaimer that I'm still a noob, too.

I gave my main recommendation there, for transceiver. I haven't done the research to have a model or brand in mind, but a cheap SSB (single side-band) radio seems like it should exist, given that you can make such a device with just 7 transistors. Any remotely modern computer will be able to generate an audio signal that, when mixed up to RF the way a SSB radio does, will look like the mode of your choice. Software-wise, I've really liked working with GnuRadio so far.

Amps go for a lot more new, because they have to handle both radio frequencies and >100W powers, and do so without causing distortion. Ham radio is a dying art, so poking around for ones at estate sales or similar seems promising. 100W is generally the recommended minimum if you don't want to be frustrated.

For the feedline, assuming you're doing coax, the design tension is between bendability and DB/meter attenuation. For radio 50 ohm impedance is standard, not 75, so you can't reuse stuff from cable TV without transformers. (Impedance matching is very important, as you'll learn getting a licence)

For the various accessories you may need to connect cables, amps, antenna wires and maybe filters, Amazon. They even have the obscure stuff I've needed for my direct sample radio.

All the prefab antennas I've seen seem ludicrously expensive, given that it's a chunk of ordinary metal, so probably skip that and cut your own. Antenna recipes are all over the place on ham homepages. If you're doing a bunch of non-resonant antennas, a tuner will save you time, but they cost as much as an amp. Everything that works at the high-power end is expensive.

[–] CanadaPlus@lemmy.sdf.org 17 points 1 day ago* (last edited 1 day ago) (3 children)

Yeah, ham radio. If I was doing it all over again, I'd go for the most basic SSB radio I can find that plugs in to a computer sound card - that should in theory be able to do anything reasonable. You'll also need feed lines, an amp and a large-ish antenna, which is where things get a bit more technical hardware-wise, especially if you're in an apartment or have something like an HOA, but it nothing you can't figure out.

And yes, a licence. So far I've found the requirements pretty reasonable in my jurisdiction, they relate to not frying yourself or your equipment, and how not to be a menace to other people sharing the radio bands. You used to need to learn Morse code fluently enough to pass a practical test, but most places have gotten rid of that.

[–] CanadaPlus@lemmy.sdf.org 1 points 1 day ago* (last edited 1 day ago)

YT link, or URL fragment to add to your favourite IV instance: watch?v=6gbTDZcOkRw

Eh, pretty heavily derived. It's probably more like heavy sampling.

[–] CanadaPlus@lemmy.sdf.org 1 points 1 day ago

You know, I kinda wonder if there's been more classic threads since the APIocalypse, but not enough to actually endure Reddit.

[–] CanadaPlus@lemmy.sdf.org 1 points 1 day ago* (last edited 1 day ago)

Ah! That makes sense. I wasn't expecting мимо to act like a noun in this way. Большое спасибо.

[–] CanadaPlus@lemmy.sdf.org 2 points 2 days ago* (last edited 2 days ago) (2 children)

Cbat by Hudson Mohawke. Is it actually about sex? Let's find out.

[–] CanadaPlus@lemmy.sdf.org 1 points 2 days ago* (last edited 2 days ago) (2 children)

вообще мимо

Please help, я это не понимаю.

[–] CanadaPlus@lemmy.sdf.org 1 points 2 days ago* (last edited 2 days ago)

The whole (Mediterranean) universe.

[–] CanadaPlus@lemmy.sdf.org 2 points 2 days ago* (last edited 2 days ago)

Not surprised. The Russian Wikipedia page on it is just a stub. The English one is actually longer.

I can't find any online introductions to it or compilers for it either, in English or написал по-Русски. Or Ukrainian for that matter, assuming I'd know it if I see it, although the Wikipedia page is longer.

[–] CanadaPlus@lemmy.sdf.org 5 points 3 days ago* (last edited 3 days ago)

Kudos to the people who actually adhered to the "unique" part of this. No, you're not unusual for hating money men. It's only a matter of time until someone posts "cops".

The entire entertainment industry is gross and depressing seen from anywhere close to the inside, but I'm not sure I'd really say I oppose it in concept.

[–] CanadaPlus@lemmy.sdf.org 6 points 3 days ago

Whoosh!

Have an sympathy upvote.

[–] CanadaPlus@lemmy.sdf.org 15 points 3 days ago* (last edited 3 days ago) (2 children)

Гарантийный без ошибки памятей!

I unironically think it would be hilarious to write a borrow-checked version of Адрес. (The Soviet version of C - or rather C is a version of it, given that Адрес was first compiled in '55)

 

cross-posted from: https://lemmy.sdf.org/post/21879517

A link to the preprint. I'll do the actual math on how many transitions/second it works out to later and edit.

I've had an eye on this for like a decade, so I'm hyped.

Edit:

So, because of the structure of the crystal the atoms are in, it actually has 5 resonances. These were expected, although a couple other weak ones showed up as well. They give a what I understand to be a projected undisturbed value of 2,020,407,384,335.(2) KHz.

Then a possible redefinition of the second could be "The time taken for 2,020,407,384,335,200 peaks of the radiation produced by the first nuclear isomerism of an unperturbed ^229^Th nucleus to pass a fixed point in space."

 

A link to the preprint. I'll do the actual math on how many transitions/second it works out to later and edit.

I've had an eye on this for like a decade, so I'm hyped.

Edit:

So, because of the structure of the crystal the atoms are in, it actually has 5 resonances. These were expected, although a couple other weak ones showed up as well. They give a what I understand to be a projected undisturbed value of 2,020,407,384,335.(2) KHz.

Then a possible redefinition of the second could be "The time taken for 2,020,407,384,335,200 peaks of the radiation produced by the first nuclear isomerism of an unperturbed ^229^Th nucleus to pass a fixed point in space."

 
 

People new to federation are wandering elsewhere. If the logged-in screen is anything like what I see as a guest, I'm not surprised. I found this through my own instance's search feature.

 

I've been playing with an idea that would involve running a machine over a delay-tolerant mesh network. The thing is, each packet is precious and needs to be pretty much self contained in that situation, while modern systems assume SSH-like continuous interaction with the user.

Has anyone heard of anything pre-existing that would work here? I figured if anyone would know about situations where each character is expensive, it would be you folks.

 

We have no idea how many there are, and we already know about one, right? It seems like the simplest possibility.

 

This is about exactly how I remember it, although the lanthanides and actinides got shortchanged.

 

Unfortunately not the best headline. No, quantum supremacy has not been proven, exactly. What this is is another kind of candidate problem, but one that's universal, in the sense that a classical algorithm for it could be used to solve all other BQP problems (so BQP=P). That would include Shor's algorithm, and would make Q-day figuratively yesterday, so let's hope this is an actual example.

Weirdly enough, they kind of skip that detail in the body of the article. Maybe they're planning to do one of their deep dives on it. Still, this is big news.

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