John, If both side have good Doppler correction then it can be done, but you have to choose the correct mode as there are other issues even if the Doppler correction is perfect, especially when the range is changing at its maximum, for example as the satellite passes overhead.
Simon Brown G4ELI http://v2.sdr-radio.com -----Original Message----- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of John / NS1Z Sent: 20 July 2014 11:46 To: Phil Karn; Paul Stoetzer Cc: amsat-bb@amsat.org Subject: Re: [amsat-bb] going digital Is there some reason why a digital signal cannot be passed thru an analog/linear transponder? What goes in is what comes out. It seems the lack of transponder bandwidth limits the digital signal experimenter... Maybe that is why commercial transponders on satellites are linear. They can take any modulation and retransmit it : AM, FM, PM or CB The biggest problem would be the taxi-cabs etc -----Original Message----- From: Phil Karn Sent: Saturday, July 19, 2014 4:24 PM To: Paul Stoetzer Cc: amsat-bb@amsat.org Subject: Re: [amsat-bb] ANS-199 AMSAT News Service Special Bulletin - AMSAT Fox-1C Launch Opportunity Announced On 07/19/2014 12:28 PM, Paul Stoetzer wrote: > Are FM repeater satellites what we all want in orbit? No. Personally, > I'd like a Mode J linear transponder in a sun synchronous circular > orbit of about 2,000km (if we can't get anything to HEO). Getting a launch opportunity is difficult and expensive. Going digital is not. _______________________________________________ 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 _______________________________________________ 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
