[amsat-bb] If you can't beat them... (QRM)

[Emily Clarke <w0eec@xxxxxxxxx>]

I've been very reticent about sending out something like this - please 
don't kill the messenger.

This evening on the FO-29 the QRM from Mexican illegal stations 
transmitting FM into the satellite band was unbelievable! I couldn't get a 
SSB signal over the FM QRM. (Take this as a sign of righteous indignation.)

In the past, the "rule of thumb" communicated to me by my elmers when I was 
a satellite "pup" was for everyone to set their transmitter to 145.950 and 
tune their receiver to about 435.860.  (Not the One True Rule - tnx to 
KB5MU) but it was enough for manual tuners to predict how to keep 
"close".  Unfortunately I think the time for this has changed.

QRM from both south of the border and in the US (meaning stupid people who 
set up simplex repeaters for VOIP) on frequencies that they think is clear 
seem to have one thing in common - they have rigs that are FM and 6KHz 
bandwidth, and they have tuning steps that are fairly wide spaced 
(25KHz).  Moving away from them seems at this time to be the only real 
solution. At least until the authorities finally realize that our dedicated 
frequencies need protection (probably never.)

So for now, I'd like to propose the following to help everyone deal with 
the frustration.  Set your initial frequency for FO-29 that used to be 
145.950 uplink to 145.945.  This will move your initial downlink from 
approximately 435.860 to approximately 435.865.  Even if there is QRM, 
(which will still drag the AGC down - can't be helped) it will move you at 
least 3KHz away from the QRM. This should help keep most people out of the mud.

73,

Emily



---------------------------------
W0EEC - CM87tm
AMSAT Area Coordinator - San Francisco Bay Area
http://www.projectoscar.net    http://www.PlanetEmily.com

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