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Martin Potter September 17th 04 12:58 AM


"Jer" ) writes:
If you would 'google' it up, you would find that the military prempts the
FCC and can operate just about anywhere they want without 'permission' from
the FCC. I found some military stuff right in the middle of our 450 band a
couple years ago, and challenged the operator.


In general, the military everywhere like to rely on Article 38 of the ITU
Conventions.

The first para of Article 38 pretty much says the military radio
installations of any country can do whatever they want.

But the second para says "Nevertheless these installations must so far as
possible observe statutory provisions relative to ... the measures to
be taken to prevent harmful interference [to other services] ..."

Many military people are like other people I know (present company
excepted of course HI) - as soon as they find something they like, they stop
reading, so they never get to the second paragraph of Article 38.

It may be worth reminding them occasionally that ITU Article 38 is not a
blank cheque.

.... Martin VE3OAT




gudmundur September 17th 04 05:56 AM

In article , says...

I kind of chuckled at the thought of a handful of gnat-like hams chasing
out the 800 pound gorilla Woodpecker. It's reminiscent of the guy doing
the little dance. When asked why, he said, "to chase away the lions".
"But," came the response, "there aren't any lions within thousands of
miles." "See, it works, doesn't it?" said the dancing man.

As Martin points out, the Woodpecker would sit at one frequency for a
while, then jump to another -- I heard it many times. But I hadn't
realized there were people out there congratulating themselves for
chasing it off when it did make one of its frequency jumps.

Roy Lewallen, W7EL



And any of these times that you listened, had you ever heard anyone
intentionally messing with it?? Yes, it would sit a while then move
to some other frequency. But it would sit much shorter if you screwed
with it. Geez, there were even articles written on exactly the keying
rate to chase it away. A kw and a beam on 40, and a keying rate of
just about 10hz would chase it out almost instantly, and if it came
back in short order, a second chase usually drove it off for the rest
of the evening.






Martin Potter wrote:

gudmundur ) writes:


I used to love to drive the woodpecker crazy. It was easy to chase it
out of the ham bands.



The Woodpecker changed frequency all the time anyway, whether anyone tried
to interfere with it or not. It was part of their operational plan. And
the pulses carried a PSK coded pattern to make it easier to recover the
returned echoes, sorting them out of the interference. I doubt very much
that anyone could really interfere with them when they operated.

... Martin VE3OAT




John Miles September 17th 04 10:07 PM

In article , says...

As Martin points out, the Woodpecker would sit at one frequency for a
while, then jump to another -- I heard it many times. But I hadn't
realized there were people out there congratulating themselves for
chasing it off when it did make one of its frequency jumps.

Roy Lewallen, W7EL


Truly, the human brain is the most sensitive correlator ever devised!

-- jm

------------------------------------------------------
http://www.qsl.net/ke5fx
Note: My E-mail address has been altered to avoid spam
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Gregg September 19th 04 08:36 AM

Here's the modern woodpecker :-)

http://www.raytheon.com/products/hfswr/

--
Gregg t3h g33k
"Ratings are for transistors....tubes have guidelines"
http://geek.scorpiorising.ca

K7MEM September 19th 04 02:16 PM

gudmundur wrote:
In article , says...

I kind of chuckled at the thought of a handful of gnat-like hams chasing
out the 800 pound gorilla Woodpecker. It's reminiscent of the guy doing
the little dance. When asked why, he said, "to chase away the lions".
"But," came the response, "there aren't any lions within thousands of
miles." "See, it works, doesn't it?" said the dancing man.

As Martin points out, the Woodpecker would sit at one frequency for a
while, then jump to another -- I heard it many times. But I hadn't
realized there were people out there congratulating themselves for
chasing it off when it did make one of its frequency jumps.

Roy Lewallen, W7EL


And any of these times that you listened, had you ever heard anyone
intentionally messing with it?? Yes, it would sit a while then move
to some other frequency. But it would sit much shorter if you screwed
with it. Geez, there were even articles written on exactly the keying
rate to chase it away. A kw and a beam on 40, and a keying rate of
just about 10hz would chase it out almost instantly, and if it came
back in short order, a second chase usually drove it off for the rest
of the evening.

Martin Potter wrote:


gudmundur ) writes:

I used to love to drive the woodpecker crazy. It was easy to chase it
out of the ham bands.

The Woodpecker changed frequency all the time anyway, whether anyone tried
to interfere with it or not. It was part of their operational plan. And
the pulses carried a PSK coded pattern to make it easier to recover the
returned echoes, sorting them out of the interference. I doubt very much
that anyone could really interfere with them when they operated.

... Martin VE3OAT


Personally, I don't place any stock in someone being able to chase away
the woodpecker. In the early 80s I operated from Reifenberg Germany as
DA2EU. I mostly worked 15 Meters CW. When the woodpecker came on line it
was like someone stuck a hot poker through your head phones. You felt
like a cartoon character, with the headphones bouncing away from your
head. The signal was so strong it completely swamped the receiver and
it was being swept over the entire band. They may have been sweeping
further, but that's all I was able to determine.

But each time it only lasted 3 or 4 minutes. When it went away the whole
band was quiet, and then slowly came back to life. I doubt that anyone
was able to do much to stop or deter it.

--
Martin - K7MEM
http://www.k7mem.150m.com


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