Don't trust the net too much

[Doug Hughes]

>On Wed, 12 Jul 1995, Doug Hughes wrote:
>
>> Go see Winn Schwartau talk about HERF guns sometime. He passed around
>> a picture of a device for < US$500 that could crash any computer within
>> 50 yards..  Then again, it isn't too good for the person firing the gun
>> either.. (mega EM emissions).
>
>That all depends on the power level, and the emission pattern of the 
>device, and the frequency.  I've been working within 10 feet of a dipole 
>being fed by a 1kW amplifier before, and it didn't make me sterile (but 
>it might've loosened a filling or two <grin>).
>
Agree!

>> The parts are available if you know what to get. a VERY enlightening
>> and frightening presentation. I don't think he personally has built one.
>> His presentation contained a presentation on TEMPEST emissions, and
>> low level EM field effects on sensitive equipment problems too (a PBS
>> documentary - a VERY compelling presentation of why you should never
>> use walkman/CD players/radios/electronics equipment on airplanes if
>> they say not to, and you value your life)
>
>This sounds like absolute propoganda.  If you do the calculations, you'll 
>see that a 1 watt transmitter sitting 100 feet away from your target will 
>generate an EMF less than that 1000kW ERP TV transmitter array you just 
>flew over.  If aircraft avionics were *that* sensitive, we'd have planes 
>falling out of the sky, and we don't.  Add to that the HF and VHF 
>transmitting equipment in the cockpit, plus the microwave ovens in the 
>fore and aft, PLUS the phones they have on the plane, and it adds up to a 
>sizeable amount of RF bouncing around the cabin without you and your 2m 
>talkie with it's 6 dB loss rubber duckie.
>
>Now, if every passenger fired up their 2m talkies, that might pose a 
>problem, but then again every passenger wouldn't be using one, would they?
>
>Again, sounds like "we want to totally control your environment for your 
>safety (actually, to minimize our liability)" crap.

If you saw that PBS documentary (they want $20,000 for rebroadcast by the 
way). It was an 87 or 88 or something like that. It would make you
a believer. There was a lady in a van that whenever she used her cellular
phone, her sun's breathing apparatus (lung impaired) went into alarm.
 There was another case at a hospital pre-natal care word near the main
entrance to the hospital. Several occasions when a local bus loop went
by, and the guy happened to be talking on the intercom of the bus, several
of the units in the ward went into alarm and failed (they had a tough time
tracking that one down by the way). 
 Wheel chairs for handicapped people were sensitive. They held a cellular
phone about a foot from a wheel chair control and it started spinning around
and generally going out of control. (The guy's wheel chair had gone out of
control and run him off a heavy slope once and he almost died. it was
unproven whether it was electromagnetic or just a defect).
 This just goes to show that we live in a world of electromagnetic soup.
We really don't know how it effects the body long term, or whether, having
more mission or life critical electronics could be interacting with over
devices. This was the theme of the program.
 Another example was on an airplane (several of them.. older ones mostly
I believe) pilots would occassionally lose instruments (VLS, etc) when
passengers would activate portable transistor radios and such. Particularly
radios.. But there was another case involving a portable computer.. These
cases have been documented. It's a good thing the plain wasn't on a 
landing approach during a storm, or things could've gone very bad very
quickly.
 I heard about the portable computer via a different source. The guy
kept turning his computer on. The instruments would do a little dance.
The captain would tell the stewardess, she would tell the passenger, he
would turn it off for a while. Then, he would turn it on and repeat..
Until finally he refused to turn it off, so they confiscated it and
returned it at the end of the trip. Urban Legend? maybe..

 Believe what you want, but investigate the reports before dissmissing it
out of hand as propaganda. I'd rather stay alive than rely on "theoretically
it shouldn't matter." :)

Keep in mind that newer planes (767, 757) let you do anything you want
while the plane is in flight (but now while landing or takeoff), so they
probably build better instrumentation and cabin shielding into the planes
these days. If they say keep it off, chances are they have a good reason..

If you find categorical evidence to the contrary, I'm sure I would be very
relieved to see it posted here. (rather than wondering if somebody
in one of the 30 rows ahead of me might decide he knows better)

Disclaimer: I have absolutely no idea what kind of shielding goes into
an airplane nor any knowledge of building practices in the airline industry,
but that should be obvious. ;)

Well, I've posted enough on this, and I don't have any evidence besides
what I've seen and what I've heard from others. For all I know the
entire documentary was botched (it was shown on an evening newsmagazine
in the late 80's hosted by Connie Chung - British documentary). Now back 
to your regularly scheduled mailing list already in progress.

--
____________________________________________________________________________
Doug Hughes					Engineering Network Services
System/Net Admin  				Auburn University
			doug at eng.auburn.edu
		"Real programmers use cat > file.as"