[amsat-bb] Mode-S uplinks

Edward R. Cole kl7uw at acsalaska.net
Tue Jan 11 11:12:12 PST 2011

In the process of re-building my wind-damaged satellite antenna array 
and got thinking about the mode-S sats.

I will be installing a 8dBic (RHCP) patch antenna (bought from L-Com) 
and have two different Drake downconverters to chose from depending 
on what the uplink band is.  I am guessing that AO-51 is the only 
S-band sat available, currently.  I have 435 and 123 MHz IF's for 
S-band converters depending on whether the uplink is VHF or UHF, respectively.

So the question is whether mode-US or mode-VS is the norm on 
AO-51.  I can install both downconverters with a coax switch and run 
two IF coax lines, but it would be simpler to have only 
one.  Especially, since installation is at a current +3F temperature.

I am installing a downsized array from what I had up:  using 2/3 of 
my 436CP42 which I call my "436CP26", a M2-2m7 yagi, and the 
patch.  I am not re-installing the 33-inch S-band dish or the 1268 
loop-yagi this winter.  The dish was probably what caused the support 
mast to bend over (65mph winds get some credit).

73, Ed - KL7UW, WD2XSH/45
BP40IQ   500 KHz - 10-GHz   www.kl7uw.com
EME: 144-1.4kw*, 432-100w*, 1296-testing*, 3400-winter?
DUBUS Magazine USA Rep dubususa at hotmail.com
*temp not in service 

More information about the AMSAT-BB mailing list