We only run V/S and L/S, with V/S being far more common. I'd use the 435 IF. I'd also put a preamp at the feed, and the downconverter in the shack where it can be easily swapped if needed.

73, Drew KO4MA AMSAT-NA VP Operations

On 1/11/2011 2:12 PM, 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

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