[amsat-bb] Re: ISS rptr

Nate Duehr nate at natetech.com
Wed Feb 6 11:35:55 PST 2008


Auke de Jong, VE6PWN wrote:
> Anyone here have trouble with local signals bowling-over the downlink?  I've 
> got a local repeater somewhere nearby on 145.790 that prevents me from 
> hearing the ISS downlink.  I can't find the frequency listed on either 
> echlolink or irlp's websites.

What do EchoLink or IRLP have to do with the frequency chosen for a 
local repeater by the repeater trustee?  It's 100% a local problem, no 
matter what linking technology the Amateur decided to use.

Locally 145.79 is listed in our local bandplan as "Miscellaneous and 
Experimental Modes" and it's not an appropriate place for a repeater 
here.  (Colorado, USA)

145.5-146.0 MHz is also NOT part of the U.S. repeater sub-band legally, 
but no idea what your rules in Canada are.  Searched the RAC website for 
a link to your regulations, and that was ... well, useless.

Are you sure it's a repeater, or is it a simplex link into one of the 
above-mentioned systems or a link between sites or similar?

> Is there a better way to find an individual repeater?  Normally I could just 
> contact the owner by listening to the ID, but the quality of the injected 
> audio from their controller is so poor(lots of bass and deviation, 
> absolutely no treble) that I can't make out the callsign.

Probably "double-deemphasized".  The proliferation of people building 
repeaters and simplex links has really taken off now that it's seen as 
an "easy" thing to do.  Of course, if they have no idea how emphasis and 
de-emphasis work in an FM rig, they're hosed from the very start and 
don't even know it.  Then they wonder why it sounds bad.  The basics of 
FM are lost on a lot of hams these days, sadly.  Try having a discussion 
about the difference between deviation and modulation on any FM repeater 
during drive-time if you want an exercise in futility.

If it's CW, just record it and play with it in your favorite audio 
editor to tweak the audio to your liking.  With the typical display in 
that type of software, you may even be able to copy a CW ID "visually". 
  I like Audacity for this type of thing.   Free, works on most 
platforms (like great software these days should) and well, how can you 
beat free software that wins awards for how good it works?  (GRIN)

http://audacity.sourceforge.net/

If voice... well, no thoughts there.  If it's so bad you can't 
understand a voice ID, how are they even using it?

Makes me wonder if it's someone experimenting with wide-band deviation 
(wider than 5 KHz)... which while not really effective and efficient use 
of spectrum, certainly may be something that someone is playing with in 
your area.

All you can do is try to contact the owner and ask them to move it, 
explaining that they parked it right next to the downlink of ISS.  I 
doubt anyone sane would not honor your request.  Of course, there's 
plenty of completely insane/crazy hams out there... been there, done 
that.  Got the T-Shirt.

Nate WY0X


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