[amsat-bb] Re: Newbie Question on AO-51

Andrew Glasbrenner glasbrenner at mindspring.com
Sat Jan 19 20:51:50 PST 2008

Hi Terry,

AO-51 has a number of different transmitter and receivers that can be tuned 
or cross connected in various ways, as opposed to most of the other 
satellites currently operational. The QRP mode has been run in the past as a 
second independent repeater with the QRP restriction in response to 
complaints about crowding on the main repeater. Unfortunately it never saw 
more than occasional use when active, which has led us to run it much less 

Up until the beginning of last year, a 67 hz PL tone was used to only gate 
the audio on the main repeater. In theory this is a good system to limit the 
satellite to repeating amateur communications. In practice we found it 
creates significant problems when many users try to access the satellite at 
once. It also masks the ever worsening problem of non-amateur users on our 
uplinks, as well as out of band terrestrial amateur users, populating the 
uplink with things like IRLP and Echolink nodes.

When we do run the QRP repeater, 10 watts to an omni or a handheld antenna 
was the criteria. That being said, if there isn't a lot of competition, 
500mw and less can be used on the regular 435.300 repeater. Signing /QRP or 
/handheld will usually garner some extra attention too.

The best source of current information on the modes on AO-51 can be found at 
this part of the website : http://www.amsat.org/amsat-new/echo/CTNews.php

73, Drew KO4MA

----- Original Message ----- 
From: "Terry Dillard" <tdillard at gmail.com>
To: <AMSAT-BB at amsat.org>
Sent: Saturday, January 19, 2008 10:36 PM
Subject: [amsat-bb] Newbie Question on AO-51

>I am a relatively new Tech learning to work the LEOs, and have a question
> specific to AO-51. On AO-51's status page at AmSat.org, it lists a Mode 
> V/U
> (J) "QRP" frequency with no PL tone, and a Mode V/U (J) frequency with a 
> PL
> tone of 67.0 Hz.
> What's considered the maximum wattage to operate on QRP? Also, since I've
> never operated on the "PL" frequency, is it even active? Do "non-QRPers" 
> use
> it, is it available?
> Thanks for the help!
> -- 
> Terry Dillard, KI4YZI
> www.ki4yzi.com
> "Veritas Vos Liberabit"
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb 

More information about the AMSAT-BB mailing list