[amsat-bb] Re: Terrestrial QRM to FM satellites

[Nate Duehr]

On Sep 20, 2007, at 9:29 PM, Bob Bruninga wrote:

> 2) Its in the cities that the repeater density is so high that some  
> new hams might feel there is no other place to put up a local non- 
> coordinated repeater.  So we probably have a good chance of  
> somneone on this BB hearing them.

I missed if the QRM is known to be voice or if Bob's note here makes  
it sound more like it's a packet station, but if voice...

These transmissions could be coming from some of the "other things"  
-- new technologies that sound like repeaters, but aren't... that are  
popular lately on 2m FM simplex.

Auxiliary Station operation in 2m is now legal, and many newer hams  
setting up things like EchoLink and IRLP simplex stations really  
aren't very careful sometimes about where they park them in the  
band.  In most cases, it's NOT malicious, but it can sure be  
frustrating to find them and explain to them about the unintentional  
interference they might be causing.

I was on the "stop doing that kids, it's illegal" bandwagon up until  
the rule change, now I'm still on the "please, put your favorite toy  
on 222, UHF or higher, kids!  VHF is kinda "full" in most big cities,  
even if you stick to the bandplan" bandwagon.

The manufacturers really make this above-mentioned situation so much  
worse by selling VHF-only radios as "cost" or "loss leader" products  
to entice new hams into buying them.   They really need a better  
marketing plan that doesn't stuff VHF so full to the gills that  
interference can't be helped.  Please support and applaud any  
manufacturer who's UHF single band radios (if they even have any) are  
as inexpensive to purchase as their VHF's.   Right now, I don't think  
a single manufacturer of ham rigs meets that, or has even given a  
thought to what they're doing to VHF.

As a major volunteer for IRLP, I would remind folks that if it turns  
out to be something like IRLP, EchoLink etc... please don't taint  
your viewpoint of these technologies, or get overly-emotional about  
the "source" being one of those networks... the networks are just  
linking technologies, but many hams really don't know when and where  
it's appropriate to link things into simplex FM -- especially on 2m  
FM simplex.

To them, they don't even always know that there even ARE such things  
as satellite uplinks in the VHF band.  Seriously.  Strange thought to  
the AMSAT crowd, but we've run across complaints (non-satellite)  
before of IRLP simplex nodes interfering with long-standing users of  
VHF simplex frequencies.

Also keep in mind that if someone does copy something and reports it  
here to the list, the voices/callsigns they hear might not even be  
the callsigns of the operator of the "incorrectly placed" link/ 
Auxiliary Station.

You may have to tread lightly if you find out who it is, and ask them  
if they were operating via a Reflector or Conference Server during  
the timeframe of the interference, and even then, they may not know  
for sure.

The only thing you might know for sure if you listen to 145.85  
locally and hear something that's not a satellite transmission, is  
that the transmitter actually causing the interference is in your  
area... from that point, some knowledgeable and experienced sleuths  
may be required to help figure out what exactly it is... and of  
course, a good DF'ing crew doesn't hurt either!

Just thoughts.  I hope that this isn't what it turns out to be...

--
Nate Duehr, WY0X
nate at natetech.com