On Thu, 22 Nov 2007 14:09:38 -0600, Don Foreman
wrote:

On Thu, 22 Nov 2007 14:24:15 -0500, Leon Fisk
wrote:

I wouldn't be
surprised if on-board computers in vehicles went berserk and
shut down too at the levels it would most likely take.

Why do you think it would take so much power? How much power do you
think it takes to initiate an electric cap?

Hint: U.S. military caps are specified to initiate with 16.3
millijoules of energy delivered in a period of not less than 10
milliseconds nor more than 24 milliseconds. That's a power level of
between 0.67 and 1.63 watts.

This isn't to say that the notions of flails and heavy blast-proof
non-manned vehicles aren't viable or even possibly best approaches,
only to argue that while they seem to be obviously viable approaches
they are not obviously the only viable approaches.

I don't know much about blasting caps Don, but if it was as
easy as you say they would be going off all over the place
prematurely.

Wires to caps are usually twisted. It's pretty hard to couple much RF
into twisted pair. They're kept shorted at the user end until just
before detonation.

In an IED, the wires must spread enough to at least accomodate a
battery. That isn't much, but very short wavelength could do it, like
10 to 20 GHz. Very directional antennae of managable size are
possible (and usual) at those wavelengths.


I wonder if they still use blasting caps like you described
today. The use of radio type equipment has skyrocketed in
the Armed Forces. I would be concerned about them setting
off their own stuff prematurely.

Yup. I took those numbers from a 2005 spec.

The biggest problem I see with trying to do this is jamming
up your own equipment, causing either radio or vehicle
malfunction. How long do you think it will take for the
creator to use this to their advantage, ie plant the IED
knowing fully well that the Military will help detonate it
for you with a transmitting device.

Trying to create a tool to work against a morphing target
won't be simple, if not impossible. I would be curious to
know too if the majority of the IED's even use a blasting
cap or some other sort of detonator. Are they buried in a
dirt road, paved, culvert? Not knowing some of these
questions makes it even harder to suggest remedies.

I can think of lots of ways to defeat what we are trying to
create, I suspect the bad guys can too (shrug).

--
Leon Fisk
Grand Rapids MI/Zone 5b
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