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Re: fo-20 being jamed


At 02:53 PM 02/27/2000 -0800, ke6qis@juno.com wrote:
>  well if you havent guessed it by the subject line there is a
>c.b.'er type idiot on the loose jamming fo-20 by a keying a
>f.m. carrier and sweeping it back and fourth over conversations.
>  (me, w1pea, n6emp) and a few others.
>   the work around untill this idiot goes away is the ye old brick
>which worked for us.
>   just thought i would pass it along.

I was trying to work one of those passes today.  Generally, I try to keep 
my ERP to a sensible level, especially on a linear bird.

What happens on a linear transponder bird like FO20 is this:

The satellite receiver "listens" to a slice of spectrum, in the passband, 
and retransmits what it hears on another band.  Strong signals it receives 
in the passband are given a larger slice of the pie on 
retransmission.  Upping YOUR power only serves to rob MORE of the transmit 
power from the satellite.

A work around like you propose is counter productive, it will make YOUR QSO 
Q5, but will rob from another QSO elsewhere in the transponder.

The Automatic Gain Control (AGC) circuitry on the bird was pumping like 
crazy on that pass, in tune to the modulation of the over-powered stations 
gobbling up tansponder power.

Contrary to what was posted earlier about the FM birds being "damaged" by a 
powerful signal, an FM receiver is subject to "capture effect," which means 
the most powerful signal will capture the receive circuitry.  It doesn't 
matter if the "strongest" station is running 5 watts or 10,000 watts, the 
receiver is NOT punished or pushed past capture.

However, whenever power wars start on the linear birds, nobody wins, and we 
all lose; like today.

I've found the best way to deal with small minds, hell bent on anarchy, 
like the reality challenged individual precipitating this thread, is to 
ignore them, and give them zero press.  If they don't get the satisfaction 
of hearing you grumble about their antics, they will quietly go back to 
soaping windows, or tossing rotten eggs at their neighbors house.

A smart animal will not foul their own nest.  Keep your power down, and 
your standards up.  The fool will soon go where all fools go: back to 
lonely boredom.

73, Mike

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