Already discussed on the MoonNet reflector:
Subject: Re: [Moon-net] ISS communicaton NOT a GOOD idea !!!!
Hi Steve ,
Even our "big" signals are small when they arrive up there . Assume you use 1kw and 20dB antenna gain , this makes an ERP of 100kw or 80 dBm ERP, once your signal is +/- 600km further then you have about -130dB less power due the path loss (on 144MHz) , this means that your signal arrives at ISS with a level of -50dBm , so nothing to worry about .
Best regards, Kenny ON4DPX
At 07:49 PM 12/11/2007, Greg D. wrote:
I thought of doing this back in October, when all the Sputnik-1 / early satellite discussion was happening. Echo-1, and all that. But, I would think that NASA (if not the crew) would frown on a bunch of folks on the ground hurling a few megawatts EIRP at their home in outer space. If Bob had to have a bazillion levels of safety in place for the little PCSAT-2 transmitter, I would think this would be right up there in the safety category, no?
I haven't done the math yet... Are we far enough away that 1/x**2 saves us?
Greg KO6TH
Date: Tue, 11 Dec 2007 11:32:50 -0800 From: bob@evoria.net To: amsat-bb@amsat.org Subject: [amsat-bb] 144 Mhz contact made using ISS as passive reflector
http://www.southgatearc.org/news/december2007/bouncing_signals_off_iss.htm
Congrats to the DF2ZC and DH7FB on making a CW contact using the ISS as a passive reflector!
It's interesting that in the article Bernd discusses the problems with using PSK due to doppler, as well as manually having to set az and el. It seems to me that a couple of well equipped computer-controlled earth stations should be able to do this using One True Frequency principles with PSK. Wish I had the equipment to give it a try.
Bob - AE6RV _______________________________________________ Sent via AMSAT-BB@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
Share life as it happens with the new Windows Live. http://www.windowslive.com/share.html?ocid=TXT_TAGHM_Wave2_sharelife_122007 _______________________________________________ Sent via AMSAT-BB@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
73, Ed - KL7UW ====================================== BP40IQ 50-MHz - 10-GHz www.kl7uw.com 144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w DUBUS Magazine USA Rep dubususa@hotmail.com ======================================