Hello all... Not all satellite TV antennas are parabolic. A typical C-Band antenna is parabolic and aligned for one satellite. But, that could change if the feed was modified to receive multi-satellites, while the shape of the reflector remained parabolic. Or the antenna could be an off-center fed elliptical version. Satellite antennas for Dish and DirecTV are not parabolic, but they are off-center fed and either circular or elliptical. The elliptical version usually supports a feed that will cover multiple satellites. C-Band satellites in the U.S. Domestic arc are normally spaced two degrees apart, with some at 4 degrees spacing. DBS (Direct Broadcast Service) i.e. Dish and DirecTV, satellites are spaced 9 degrees apart. Clusters of satellites can be parked at one location to supply additional capacity for spot beam coverage. DBS service is located in the Ku-Band. More info at: https://docs.google.com/presentation/d/1eNMYmcNIxRFpK1PY0GqbvOfvNfzRra4fHxs8 A4hSy7o/preview#slide=id.p18 73 Don W4WJ In a message dated 10/9/2014 4:17:20 P.M. Central Daylight Time, and...@cleverdomain.org writes:
You pick up satellite TV with a parabolic dish that points at one spot in the sky where the geostationary satellite lives. A sun outage happens when the sun wanders into the focus and overloads the receiver with noise that drowns out the satellite signal (at least, it raises the noise floor enough that you can't receive the high bitrates needed for a TV picture). You pick up GPS with a whole-sky antenna that receives signals from the constantly-moving swarm of GPS satellites. It undoubtedly receives some noise from the sun, but the only factor in how much of that you get is the sun's elevation above the horizon. It's not really relevant whether the sun is "aligned with a satellite" or not. Even if it was, the satellite would be somewhere else a minute later. :) Andrew On Thu, Oct 9, 2014 at 1:40 PM, Bob Stewart <b...@evoria.net> wrote: > Two days this week, there was a 3 or 4 minute outage on DirecTV as the sun aligned with the satellite and my dish. So I was wondering what kind of effect this has on the GPS system and especially timing receivers. > > > Bob - AE6RV > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.