some goods and intermediates have large energy content, like, if you wanted to use energy from large pv farm in, say, morocco, then it might make more sense to ship bauxite in and aluminum bars out (it takes some 50MJ/kg to make aluminum)

simplicity of the system would be a factor in small, unattended installations like for space heating for single home

all of that without heat pumps too

It is a liquid that after irradiating stores that energy while still cold and can be made to release it in form of heat on demand. but also it’s low grade heat mostly useful for heating and not for electricity generation. It would be simpler to just build long range transmission lines or put energy intensive manufacturing near PV farm in sunny region

it’s transparent too so you can just put pv panel underneath to capture the rest

you get 1.6MJ/kg just by irradiating this thing, nothing else is needed and its storable for months as noncorrosive room temperature liquid

to make ammonia you need to have pv to turn light to electricity then make hydrogen out of it then make ammonia in haber process, each step generates losses and none are practical on small scale

there is a problem that it can heat itself up so hard during decomposition that it can just go on without catalyst

aaand it boils water again

The one we can mine is drawn off together with natural gas, and was produced over geological timescales as product of alpha decay of uranium

New ones, and not all if them, work this way, as in there’s tiny helium condensing unit. Older ones just let it go and require topping up every couple months (guessing by how often helium in NMR is topped up). Also every emergency shutdown invariably blows off all of helium inside

they stood no chance, never knew what hit them

dropped as cleanup-only, not allowed by their policies

i suspect that it might be vibecoded, too

there was chrome (and firefox probably?) extension that went through your all fb liked pages and unsubscribed from them so that when it’s done timeline is gone entirely. fb went after its dev, removed that extension and banned him forever because it kept people off fb https://www.businessinsider.com/facebook-bans-unfollow-everything-developer-delete-news-feed-2021-10 doing this all manually still worked back then, not sure about today

Facebook’s letter took him by surprise, he said, adding that Unfollow Everything had only 2,500 weekly active users and 10,000 downloads.

“It was definitely growing, but it wasn’t huge,” he said.

“Apart from that I just very much saw it as something that improves the Facebook experience for Facebook users,” he added, saying he got “amazing feedback” from people saying they “were using Facebook in a way that was much healthier for them.”

slightly healthier relationship with attention devouring parasite in your pocket? not on zucc’s watch, ALL contents of your skull are to be sourced from and licensed to meta platforms inc exclusively

i was thinking more like, thin external plastic shell and empty cells inside, perhaps with another thin plastic shell on inside, and internal metal shell (on plastic support?) fitting in snugly, for mechanical stability, idk 3dprinting

keeping leads short and nonmagnetic (dramatic reduction in skin layer depth) would be a good thing because of losses, but the longest object in capacitor would be just capacitor plates, and either way in wavelength terms it’s rather small. more precisely you can model it as open transmission line stub with some weird and low impedance, but it’s so small that you don’t have to. you can also make capacitor shorter and wider, or even add more layers like how vacuum variables are made. in nesting design you can get taper effect just by making inner layers longer

Found a piece about RFI and baluns, http://audiosystemsgroup.com/RFI-Ham.pdf multiple turns on ferrite aren’t really an option for VHF and up, ended up ordering extra beads (non-split)

The dielectric between the plates in this case is 0.4mm of ABS plastics (+ a bit of air in the 3d print layer lines).

in terms of losses, PP or PE is a bit better than ABS, teflon or FEP is a bit better than PP, but air is superior to either (this is part of the reason why foam coax is a thing). not sure which ones are printable, or whether it’s practical at this size, but try to introduce as many voids as possible (perhaps requires larger thickness of dielectric). it doesn’t matter much in your case, because of low power (warping of plastic because of excessive heat is probably not a problem). if your coax has solid dielectric, then by introducing enough air in 3d-print your variable might become less lossy than that

The Capacitors allows my 80cm diameter loop to tune from 20Mhz to 37Mhz. Sweeping the whole range is a bit slow due to the low RPM of the motor and takes about 6min. But that is kinda nice when fine adjusting to a frequency.

you have probably noticed that position vs resonant frequency relationship is rather nonlinear. you can get higher sweep speeds at lower end without losing much accuracy at higher end by tapering end of side plates into a triangle shape (it will get longer overall). it doesn’t matter much in your case, because it’s all approx monoband, but if you want to go multiband with this, then it’ll be a nice enhancement. similar effect happens when air variable capacitors have moving plates shaped in such a way that one end is longer than the other, and external edge has shape roughly like a section of logarithmic spiral. precise movement of variables like this is done by use of worm drive with large wheel

I am not sure what is causing this, but i assume it could be due to increase of dielectric losses in the capacitor getting bigger when more of the plates overlap because then the electric field has to flow thru a bigger area of dielectric, increasing the potential for losses.

loss tangent of dielectric is material property, that is ratio of equivalent loss resistance to capacitance should remain constant at given frequency. so i guess that losses should remain roughly the same, if dielectric is to blame, but at any rate lossy capacitor should make bandwidth broader and SWR lower. my guess would be that it’s a matter of coupling loop becoming wrong-sized or wrong-positioned at some point with change in frequency (try moving it up or down? there’s gotta be some optimum position for your entire range of interest)

i think this one was purest form of it to date https://www.404media.co/inside-the-world-of-tiktok-spammers-and-the-ai-tools-that-enable-them/

according to his own claim, and he’s selling his super secret methods. he might be just making shit up

Skin depth is larger in aluminum but not enough to balance out its lower conductivity, copper is better material taking all into account, in practice both are good. If opposite was true we’d use lead or zinc for conductors. There are satellite microwave parts made out of aluminium (low weight) coated sequentially with zinc (bonding layer), copper (better conductivity), thin layer of silver (even better conductivity) and then gold (actually not thick enough to contribute, this one is for corrosion protection)