I also observed something like this the other day. I wondered about its cause, but as I was actually doing something else at the time, I completely forgot about it.
There were, as you note, strong SSB signals around the beacon freq during the AO-73 pass. Cheers, Darren, G0HWW On 06/12/13 15:47, n0jy wrote: > Good thought, David. I do have the settings FCD Centre Frequency set > for 145945. But I also have the auto tune range limited to 34599-44854 > kHz which should only let the auto tune catch approximately 145931 to > 145941 kHz. So it should not be (nor do I observer it to) tuning any of > the transponder portion. It is always locked on the beacon as > identified by the hump and beep "spikes" as I watch it. > I do not hear FMing on the beacon. It sounds like it should, but it is > covered by a stronger SSB signal, basically. And it appears that the > combined doppler shift of the beacon and the signal make them move > across each other such that the QSO eventually passes by but then > another can come up and do the same. > Overloading the FCD maybe? I do have a preamp on, maybe I'll try it > tonight without the preamp. The reason I use the preamp is that when I > initially set up, I could not get a solid spectrograph (it blinked on > and off) unless I had the preamp on. I believe that was related to the > version of Dashboard I had at that time as observed by a friend who had > seen the same thing when he just got his FCD Pro + the other day, but it > disappeared when he upgraded his Dashboard. Preamp is off now, I will > see what happens this morning and tonight. > > 73 > Jerry > N0JY > > On 12/6/2013 2:47 AM, g0...@aol.com wrote: >> >> That's an interesting observation Jerry. Not something we saw during >> commissioning the satellite. >> A possible cause would be image response of the dongle. Do you have >> the 'zero frequency' somewhere between the beacon and the transponder >> passband? e.g. 145.945 or off to one side e.g. 145.920? >> >> Other possibility is a large signal in the transponder passband >> causing the beacon to FM. Is the modulation 'FM' or does it decode >> as SSB? >> Thanks >> David G0MRF >> >> >> -----Original Message----- >> From: n0jy <n...@n0jy.org> >> To: AMSAT-BB <amsat-bb@amsat.org> >> Sent: Fri, 6 Dec 2013 4:40 >> Subject: [amsat-bb] AO-73 QSOs on the beacon? >> >> >> During the eclipse passes while copying telemetry with my Funcube Dongle >> Pro + I am hearing SSB QSOs on the beacon frequency. >> They usually "walk" across it but what puzzles me is that the website >> info indicates that the transponder passband is well away from the >> beacon frequency. >> Am I experiencing some weird stuff with my Dongle or is it possible for >> stations to work on an uplink that puts their downlink on the beacon >> frequency? >> >> Thanks, >> Jerry >> N0JY >> _______________________________________________ >> 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 >> >> > > _______________________________________________ > 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
