4 ms·

They still sell them today. They're called Nuclear Event Detection (NED) chips. It detects a spike in voltage from the air and drops all power to everything,

by bhollan 10y ago

They still sell them today. They're called Nuclear Event Detection (NED) chips. It detects a spike in voltage from the air and drops all power to everything, acting as an instantaneous power interrupt for everything you care about. I used to test them for Lockheed all the time on stuff that flies on stealth aircraft. There is a very specific sequence of events with very tight specs they have to pass, the whole thing is over in 250 ms, and that includes the shutdown duration.

bhollan 10y ago
http://www.maxwell.com/products/microelectonics/space-nuclear-event http://www.maxwell.com/products/microelectonics/space-nuclea...
superuser2 10y ago
How do you test such a thing? Small nukes?
- bhollan 10y ago
  All it's measuring is for a voltage spike. The ones we had had a real input pin and a test input pin. You hook up an O'scope to the output, supply a one-shot signal to the test pin, and check to make sure the output did what it was supposed to in the allotted time.
- whoopdedo 10y ago
  Large radio antennas can create electromagnetic pulses like what you'd get from a nuke blast. I lived not too far from a site that tested them[1][2]. Just before it was decommissioned there were a lot of news articles written about how they did the testing. I can't find any photos now, but they're out there somewhere. It's now a wildlife refuge.. [1]: http://www.globalsecurity.org/military/facility/woodbridge.htm http://www.globalsecurity.org/military/facility/woodbridge.h... [2]: http://eservice.pwcgov.org/library/digitallibrary/hsdw/A_Folder/ArmyEMPSimulatorOp76-392/pdfs/armyEMPsimulatoropPropHistA76-0392.pdf http://eservice.pwcgov.org/library/digitallibrary/hsdw/A_Fol...
cm2187 10y ago
Would dropping power help? I thought the way the nuclear blast damages electronic circuits was by inducting large electric currants which would burn the components. If that's the case it doesn't really change anything whether the circuit was active or not at the time of the blast.
- bhollan 10y ago
  You can quite easily shield all your components from outside pulses. However, if you're processing signals from the air (like in the case of Radar systems, the ones I worked on), your stuff could quite easily get fried. Like an amp could get overloaded, a processor could get fried, a line could get burned, all kinds of things could go wrong. But the best thing you can do is have everything off. If you're close enough to a nuke that stuff that's off gets fried, your electronics are probably pretty low on your list of priorities.

by bhollan 10y ago

bhollan 10y ago

http://www.maxwell.com/products/microelectonics/space-nuclear-event http://www.maxwell.com/products/microelectonics/space-nuclea...

superuser2 10y ago

How do you test such a thing? Small nukes?

bhollan 10y ago
All it's measuring is for a voltage spike. The ones we had had a real input pin and a test input pin. You hook up an O'scope to the output, supply a one-shot signal to the test pin, and check to make sure the output did what it was supposed to in the allotted time.
whoopdedo 10y ago
Large radio antennas can create electromagnetic pulses like what you'd get from a nuke blast. I lived not too far from a site that tested them[1][2]. Just before it was decommissioned there were a lot of news articles written about how they did the testing. I can't find any photos now, but they're out there somewhere. It's now a wildlife refuge.. [1]: http://www.globalsecurity.org/military/facility/woodbridge.htm http://www.globalsecurity.org/military/facility/woodbridge.h... [2]: http://eservice.pwcgov.org/library/digitallibrary/hsdw/A_Folder/ArmyEMPSimulatorOp76-392/pdfs/armyEMPsimulatoropPropHistA76-0392.pdf http://eservice.pwcgov.org/library/digitallibrary/hsdw/A_Fol...

cm2187 10y ago

Would dropping power help? I thought the way the nuclear blast damages electronic circuits was by inducting large electric currants which would burn the components. If that's the case it doesn't really change anything whether the circuit was active or not at the time of the blast.

bhollan 10y ago
You can quite easily shield all your components from outside pulses. However, if you're processing signals from the air (like in the case of Radar systems, the ones I worked on), your stuff could quite easily get fried. Like an amp could get overloaded, a processor could get fried, a line could get burned, all kinds of things could go wrong. But the best thing you can do is have everything off. If you're close enough to a nuke that stuff that's off gets fried, your electronics are probably pretty low on your list of priorities.