[amsat-bb] Re: Terrestrial QRM to FM satellites
nate at natetech.com
Thu Sep 20 23:36:25 PDT 2007
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
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/
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
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
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