[amsat-bb] Re: Mode-S uplinks

Mark L. Hammond marklhammond at gmail.com
Tue Jan 11 13:29:02 PST 2011

Hi Ed,

Drew's reply covered it well.  The 435-IF would be my first recommendation, and his thought about putting a preamp outside, downconverter inside is a fine one.  


Mark N8MH 

At 10:12 AM 1/11/2011 -0900, Edward R. Cole wrote:
>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 

Mark L. Hammond  [N8MH] 

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