Federal offense to shoot down a federally-owned and operated drone?
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What about coating the circuitboard with solder paste, stacking SMD caps on it with one end, then putting another pasted circuitboard on top, and running the sandwich through reflow?
But I thought more along the lines of foil-wound caps.
I thought about several methods for cathode heating, in addition to the classical resistive kind. Two of the possibilities are using a laser and an induction heater. This way thereās no filament to burn out.
Possibly to remove other gases in the outer layer of the glass? Was the helium going in-out or outside-in? Would an elevated temperature be needed - then there could be issues with ions moving through the glass, and they could be swept off (or enriched in) the top layer? What was the failure mode when this was not done, this could suggest a lot?
I thought about a ceramic body, and the top and bottom parts (holding the armatures) indium-soldered to the ceramics. In a way thatād make it easy to disassemble and rebuild the tubeā¦ Or possibly using remeltable solder glassā¦
Thought also about an integrated ion pump, for achieving and maintaining high vacuum even in case of minor leaks or outgassing. Possibly using zirconium plates with integrated heater for the thyratrons, to desorb the hydrogen (or deuterium) while retaining the other molecules. Possibly with another heated zirconium (or uranium) piece to store hydrogen and release it to desired pressure regulated by heating the absorber; cool the absorber, remove as much hydrogen as possible, run the ion pump to shoot the ions into the second block of zirconium, use the mobility of the hydrogen atoms to selectively oust them from that block once the pumping is done. If weād want to complicate things, a cryotrap could be also useful thereā¦
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I donāt think thatās what it meant, but I see above that the āfederal offenseā thing is contested anyway.
This is basically what a trigatron is. They require periodic rebuilding, but the electrodes gradually get sputtered across the ceramic so rebuilding includes stripping the ceramic of all metal, I believe. The result is that rebuilt trigatrons werenāt that much cheaper than new ones.
The blue flash when they go off is pretty.
Thyratrons - I wouldnāt bother making your own.
e2v
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Acid bath could handle that, Iād say.
Optionally, what about plasma-etching the deposits away, and moving the ions by electric or magnetic field to collection plates?
Some local laser and tokamak folks complain about the export paperwork (and additional costs) needed to get the bigger switches. The tech should get liberated out of the dirty claws of the bureaucrats and made cheap-as-beer and free-as-speech and available for every garage in the entire world.
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Those laws were written to protect manned aircraft, not drones, and so far, those laws havenāt been tested in court, with respect to drones. In fact the FAA is considering removing that protection.
People have shot down drones, and often get arrested for it, but so far, not for violating federal laws.
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If the aircraft is flying under 100 foot altitude, how about a vortex cannon?
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Certainly worth trying, Iād say!
Iāve seen other people recommend 20-gauge bird shot, which is a lot smaller than this 12-gauge.
The big advantage is that the bits of shot that miss are likely to slow down enough not to do much damage by the time they get back to the ground, plus more pieces of small shot rather than fewer bigger pieces are generally an advantage for small drones, where any hit is going to make a difference so being more likely to get some hits is a win. At least this stuff is steel, so thereās no lead-poisoning risk like there is with traditional lead shot.
For short distances, a less-lethal solution is a gun that fires a net, or a hand-thrown net of some kind. Or a garden hose with a long enough range.
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Bird shot is harmless falling back to the ground. Normal bullets wonāt hurt you falling straight down, but if they come in at an angle they can retain enough speed to kill you.
But bird shot for one isnāt that fast, its doesnāt go that far (compared to a bullet), and it is harmless falling back down. I doubt buck shot would hurt you either. Slugs at an angle could potentially, how ever.
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Those rules are there to hinder nuclear proliferation.
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Should I care? They also hinder progress in lasers, in fusion, in accelerators, and in all the pulsed power related fun. Thatās more important. The slapper detonators can be actuated with semiconductors these days, the cat is out of the bag already.
And donāt get me started about thermal imagers and all other kinds of sensors that some bureaucrat decided to be crippled. We need ion beam stuff for painting sensor arrays layer by layer without needing for finicky lithography. Yes, ion beam deposition is way slower - and thatās why we need such ā3d nanoprintersā in every garage as well, and a plethora of downloadable designs. And integrated mass spectrometers in the ion feed, so you wonāt need insanely pure chemical feedstocks, just purify them in-situ and throw away the wrong-mass molecules/atoms.
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I logged in just to like your comment, and I am SO lazy!
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I wish you one high-end goose in your immediate future. Cheers!
I was prepared to suspend quite a bit of disbelief, recalling the ludicrous āNOS!ā scene from the first movie, but the ESD harpoon topped even that! Omgā¦
And no doubt of robbers as well!
And no doubt that it would find its way to the black market.
If such thing gets deployed, EMP/HERF hardening of vehicles could become a quite interesting niche business, tacked onto the armored cars one.
(And weāre back at the pulsed power, as weāll need rigs for testing the mods. You cannot go without testing.)
I heard a rumour about a case of some robbery where the buildingās alarm was disabled in a drive-by with a high-power (multikilowatt) transmitter that fried the electronics. No wonder, with the long wires (I did a few gigs installing these, aeons ago) and substandard hardening.
I always have wondered why intruders donāt just put a stun gun on the nearest sensor/alarm wire they find. Plenty of installations where that wouldnāt be enough of course, what with wireless, separate cameras, redundancy etc, but still an easy step in that direction.
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Itās not that easy. Damaging electronics this way is hit or miss. You can disable the core unit or just part of the sensor bus.
Could be worth doing some investigations.
Thereās a good chance that you get a short circuit on the bus. If you cause reverse breakdown of the ESD protection diodes, or dissipate enough energy in that part of the chip, the diode āspikesā - a filament of aluminium flows from the contact pad through the junction. Voila, the pin failed short. (The junction can also fail open, or the bonded wire can burn with the same effect.) The tantalum capacitors, on the power bus, tend to fail short as well.
For the stun gun you also need a high impedance to develop the high voltage across the terminals. The HV generators donāt have much power, being battery voltage/current/capacity limited. Youāll need an air gap for the HV to develop, and the breakdown used as a switch. An additional capacitor over the terminals of the stun gun would also help.
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Begun, the drone wars have.
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