4 ms·

Pocketable wasn't in my mental spec, agree this is a good idea. You can also inset them. Marketing a portable as Kofi-proof is a neat marketing angle ;) Depen

Pocketable wasn't in my mental spec, agree this is a good idea. You can also inset them. Marketing a portable as Kofi-proof is a neat marketing angle ;) Depending on your radio frequency perhaps you could put your RF behind your screen to get signal out, or use a slot as the antenna, or have a fold-out or telescopic antenna, or have a screw-on antenna port exposed when you open the thing, or some combination thereof. Aluminium's fine for cases, cheap, light, castable, extrudable, cheaply machined, and readily anodized. Steel won't rust for ages if it's of a decent chemistry and either treated and/or oil is used when the thread is mated. Even steel that appears heavily rusted after many decades of total abuse can be restored quite easily to a good state in many cases. I mean people had multi hundred year old wooden structures ... I don't think an embedded steel thread with an oil surface coating is going to disappear overnight. As a learning project I recently restored a 1980s drill press, that's basically 40 years old which is ~most of your target length, it had apparently been left with exposure to moisture for 20+ years, and was mostly intact. The net result of the learning was it's not worth restoring old drill presses, but I sure learned a lot! For maximum chip shelf life, you want to store them in nitrogen or some similar inert gas. With Wikipedia and survivalist content modules you could market this to the prepper crowd. Of course long distance radio would be an add-on. As would the radio direction finding hardware, encryption, etc. I still like the pneumatic idea. 100% of existing bicycle pump hardware becomes your viable charging interface. Speaking of which, a low profile wheel based generator would be a good add-on module.

kragen 2y ago
those are good ideas about antennas i hadn't actually considered machining it out of an aluminum billet. you might be right that it would be adequately stiff, even if it's much less stiff than glass-fiber-reinforced epoxy. it's much heavier than epoxy, but only slightly heavier than glass, and of course most of its grades are enormously less brittle
kragen 2y ago
oh, i don't know why i didn't answer the stuff about steel and preppers and pumps; maybe it was a brain fart or maybe you edited it in later. i'll try to answer later
- contingencies 2y ago
  Yeah it was a few edits. I often stay on a theme awhile once consciously captured, resulting in a re-read and new ideas/tweaks. Ninja skill: trainable psycho-inertia, AKA "focus", now perhaps ostracized as a 'spectrum member' activity, I believe it was merely associated with clarity of thinking and general education in the 19th and early 20th centuries.
kragen 2y ago
so, with respect to steel, i think a steel case in a sweaty pocket will rust rather quickly and comprehensively, even if it's a good steel. often alloying elements that improve steel's mechanical properties make it more prone to rust rather than less so i'm guessing the drill press was not in working condition after the 20 years of moisture, and i'm assuming you mean something like 'in a basement with relative humidity that reached 100%' or 'with the bottom resting on moist soil' and not 'under dripping water for 20 years' or 'underwater for 20 years' i don't really have a good way to machine steel anyway, and it's inconveniently heavy. aluminum is amenable to wood rasps and drills i think probably embedded in silicone or paraffin wax or something would be better than just stored in nitrogen. gottta be careful of static buildup tho while i sympathize with preppers in some ways (i, too, value autonomy) i think they might be a hard group to market to. a friend of mine occasionally reads survivalist board forum and there's a lot of toxic ultra-right-wing stuff there; i don't want to be lynched for not supporting trump you can of course do secure encryption on any general-purpose computer unless you're trying to defend against side-channel attacks. i ran pgp on a 286, and we have more efficient algorithms now long-distance radio is potentially interesting but i agree that it's probably a different piece of hardware; short wavelengths can only go short distances unless they're bouncing off the moon or something, and you need a long antenna to transmit long wavelengths efficiently, although efficiency isn't a significant concern for reception (at transcontinental-capable wavelengths radio noise is a bigger concern than noise generated inside your amplifier). so for long-distance radio you probably need a large, fixed antenna installation rather than a pocket computer my concern with pneumatic-to-electric power is that it's probably hard to make reliable. but i don't really know
- contingencies 2y ago
  For the radio, ask a HAM. I'm sure they can workshop something out of nothing and turn a clothes line in to a global command center... anyway yes, the size of long distance antennae will prohibit having them internal. One could include an SDR module but why not make it an add-on? On pneumatics, https://en.wikipedia.org/wiki/Compressed-air_energy_storage https://en.wikipedia.org/wiki/Compressed-air_energy_storage suggests 50-70% efficiency at utility scale, with China leading. https://www.csiro.au/en/research/technology-space/energy/Energy-storage/Underground-compressed-air-storage https://www.csiro.au/en/research/technology-space/energy/Ene... suggests 65% with 75% assumed aspirationally feasible. https://www.resilience.org/stories/2018-05-18/ditch-the-batteries-off-grid-compressed-air-energy-storage/ https://www.resilience.org/stories/2018-05-18/ditch-the-batt... suggests 75-85% but is likely non-holistic. https://www.signal.it/en/products/case-history-pneumopower/ https://www.signal.it/en/products/case-history-pneumopower/ suggests a small-scale implementation has been successfully productized. Indicatively at <=7 bar pressure they achieved post-loss output of DC24V@12W with a ~300g device. Since only a fraction of this is required, it should be possible to drop to ~50g with some loss of efficiency. Tiny motors are inexpensive as numerous factories compete for business, but they can fail so a replaceable setup external to the body would be preferable. Since you only need a very small amount of current, something like a small compressed air canister could then presumably store many months worth of power. It would need to activate the air source for recharging only sporadically. This could be done using physical input from the operator and an NC-type valve in order to sidestep the flat-start problem, with a parallel option for electronic actuation. Perhaps steampunk social networking would be a better market. One imagines darkly clad figures sneaking around urban environments clandestinely sneaking power top-ups from from random vehicle tyres...

kragen 2y ago

those are good ideas about antennas i hadn't actually considered machining it out of an aluminum billet. you might be right that it would be adequately stiff, even if it's much less stiff than glass-fiber-reinforced epoxy. it's much heavier than epoxy, but only slightly heavier than glass, and of course most of its grades are enormously less brittle

kragen 2y ago

oh, i don't know why i didn't answer the stuff about steel and preppers and pumps; maybe it was a brain fart or maybe you edited it in later. i'll try to answer later

contingencies 2y ago
Yeah it was a few edits. I often stay on a theme awhile once consciously captured, resulting in a re-read and new ideas/tweaks. Ninja skill: trainable psycho-inertia, AKA "focus", now perhaps ostracized as a 'spectrum member' activity, I believe it was merely associated with clarity of thinking and general education in the 19th and early 20th centuries.

kragen 2y ago

so, with respect to steel, i think a steel case in a sweaty pocket will rust rather quickly and comprehensively, even if it's a good steel. often alloying elements that improve steel's mechanical properties make it more prone to rust rather than less so i'm guessing the drill press was not in working condition after the 20 years of moisture, and i'm assuming you mean something like 'in a basement with relative humidity that reached 100%' or 'with the bottom resting on moist soil' and not 'under dripping water for 20 years' or 'underwater for 20 years' i don't really have a good way to machine steel anyway, and it's inconveniently heavy. aluminum is amenable to wood rasps and drills i think probably embedded in silicone or paraffin wax or something would be better than just stored in nitrogen. gottta be careful of static buildup tho while i sympathize with preppers in some ways (i, too, value autonomy) i think they might be a hard group to market to. a friend of mine occasionally reads survivalist board forum and there's a lot of toxic ultra-right-wing stuff there; i don't want to be lynched for not supporting trump you can of course do secure encryption on any general-purpose computer unless you're trying to defend against side-channel attacks. i ran pgp on a 286, and we have more efficient algorithms now long-distance radio is potentially interesting but i agree that it's probably a different piece of hardware; short wavelengths can only go short distances unless they're bouncing off the moon or something, and you need a long antenna to transmit long wavelengths efficiently, although efficiency isn't a significant concern for reception (at transcontinental-capable wavelengths radio noise is a bigger concern than noise generated inside your amplifier). so for long-distance radio you probably need a large, fixed antenna installation rather than a pocket computer my concern with pneumatic-to-electric power is that it's probably hard to make reliable. but i don't really know

contingencies 2y ago
For the radio, ask a HAM. I'm sure they can workshop something out of nothing and turn a clothes line in to a global command center... anyway yes, the size of long distance antennae will prohibit having them internal. One could include an SDR module but why not make it an add-on? On pneumatics, https://en.wikipedia.org/wiki/Compressed-air_energy_storage https://en.wikipedia.org/wiki/Compressed-air_energy_storage suggests 50-70% efficiency at utility scale, with China leading. https://www.csiro.au/en/research/technology-space/energy/Energy-storage/Underground-compressed-air-storage https://www.csiro.au/en/research/technology-space/energy/Ene... suggests 65% with 75% assumed aspirationally feasible. https://www.resilience.org/stories/2018-05-18/ditch-the-batteries-off-grid-compressed-air-energy-storage/ https://www.resilience.org/stories/2018-05-18/ditch-the-batt... suggests 75-85% but is likely non-holistic. https://www.signal.it/en/products/case-history-pneumopower/ https://www.signal.it/en/products/case-history-pneumopower/ suggests a small-scale implementation has been successfully productized. Indicatively at <=7 bar pressure they achieved post-loss output of DC24V@12W with a ~300g device. Since only a fraction of this is required, it should be possible to drop to ~50g with some loss of efficiency. Tiny motors are inexpensive as numerous factories compete for business, but they can fail so a replaceable setup external to the body would be preferable. Since you only need a very small amount of current, something like a small compressed air canister could then presumably store many months worth of power. It would need to activate the air source for recharging only sporadically. This could be done using physical input from the operator and an NC-type valve in order to sidestep the flat-start problem, with a parallel option for electronic actuation. Perhaps steampunk social networking would be a better market. One imagines darkly clad figures sneaking around urban environments clandestinely sneaking power top-ups from from random vehicle tyres...