Re: IED Detection - What's the Latest


"Dave Head" <rally2xs@xxxxxxx> wrote in message
news:bm6o53l4tn8pm1l2qk7s2p12nrieleejrq@xxxxxxxxxx

There's a self oscillating diode called an Osaki or 'tunnel' diode.

Connect it across a battery with a couple of other bits and it free runs
in
the RF band.

Buy a couple of thousand and attach them to batteries and spread them
about
and drive the clever technical people insane.

This stuff isn't rocket science, it's absolutely basic. I was taught
about
building these things in my first year of training. I just happened to be
taught by an ex RAF radar man who'd made the things to send radar detector
systems insane.

All this stuff has been thought about by some clever people for decades...

Run a UAV or other remote control device down the road before dawn.
Measure
the frequency of each oscillator you encounter. Do it again after
sunrise. Any
such cheap oscillator is going to drift its frequency badly as the day
warms
up. Communications receivers have to have stable local oscillators for
reliable operation, even FRS radios. Any oscillator you measure after
sunrise
that is, say, 25 parts per million from the frequency you measured it the
1st
time is probably your bomb trigger. Anything that isn't, you can probably
ignore.

Doesn't mean there aren't any IEDs there, since they could be triggered by
a
long wire, pressure switch, IR device, etc. but the radio triggers are now
a
little more obvious.

You can at least force 'em to use expensive oscillators if this is going
to
work, and nobody's got unlimited money.

No, you force them to buy a bucket full of cheap crystals...

Anyway, hardware purchase isn't a major factor in any of this. As with
most military operations involving irregular forces the major costs are
people based rather than equipment.

Feeding, housing and clothing someone covertly costs more than any
improvised bomb.

They're not blowing people up ten or twenty times a day, each cell is
probably launching an attack only every few weeks.

There is no technical solution because when you find one the bad guys will
try and use it as the trigger for an attack.

It's not a single problem, it's an evolving situation...

--
William Black


I've seen things you people wouldn't believe.
Barbeques on fire by the chalets past the castle headland
I watched the gift shops glitter in the darkness off the Newborough gate
All these moments will be lost in time, like icecream on the beach
Time for tea.




.

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