> We're not going to see another satellite with a 144 MHz yagi. > The"Mode B HEO" ship has long since sailed
Paul, The problem is there aren't any global primary Amateur-Satellite microwave bands below 24 GHz. While our allocations at 29 MHz and 144 MHz may be primary world-wide the other VHF/UHF/uW bands are not. We have seen 2400 MHz rendered useless in urban areas due to WiFi with 5840 MHz likely to go the same way. There's a 3400 MHz allocation in Regions 2 and 3 but it's not available in Region 1. 1260 MHz is now being used by the Galileo GPS system, already a German 23cm repeater has been shut down because it "interfered with a Galileo GPS receiver". We might expect further restrictions on 1260 as use of the new system spreads. http://www.southgatearc.org/articles/galileo.htm In the UK the top half of the 10 GHz satellite allocation has already been allocated to high power commercial stations. Clearly deploying some form of directional 144 MHz antenna on a 3U CubeSat will be challenging, but not necessarily impossible. 73 Trevor M5AKA On Saturday, 2 August 2014, 3:16, Paul Stoetzer <[email protected]> wrote: Gus, We're not going to see another satellite with a 144 MHz yagi. The "Mode B HEO" ship has long since sailed unless someone can come up with the $15-$20 million or more to finish and launch Phase 3E. However, given how rapidly technology has advanced, I'm not going to count out a large CubeSat (the specification covers up to 27U) getting us back to HEO some day, but it will definitely be microwave band only. 73, Paul, N8HM On Fri, Aug 1, 2014 at 9:31 PM, Gus <[email protected]> wrote: > Absolutely! Micro-miniaturization! > > But some things are difficult to miniaturize -- like a 144 MHz yagi. > > > > On 08/01/2014 09:20 PM, Bryce Salmi wrote: >> >> Innovation is often driven out of necessity. I see it everyday at work. >> Develop a baseline system that works and then optimize it. You'd be amazed >> what you could do with the small of a space to pack electronics into. >> >> Bryce >> >> >> On Fri, Aug 1, 2014 at 6:16 PM, Gus <[email protected] <mailto:[email protected]>> >> wrote: >> >> On 08/01/2014 01:24 PM, Paul Stoetzer wrote: >> >> I've noticed from reading this board's current posts and >> archives that >> there is a bias against CubeSats from some due to a belief >> that they >> are somehow inherently limited in capability, unreliable, and >> short >> lived, but there is nothing inherent in the CubeSat format >> that makes >> it that way, it's simply a standardized way to build a satellite. >> >> Their size and weight limitations restrict the type of antennas >> they can deploy, the number of solar panels they can carry, and >> simply the mass of silicon they can contain. >> >> Yes, they are cheap and launches (to LEO) are frequent, but their >> capabilities are, surely, limited by their physical nature? >> >> >> -- Gus 8P6SM >> The Easternmost Isle >> >> _______________________________________________ >> Sent via [email protected] <mailto:[email protected]>. 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 >> >> > > > -- > Gus 8P6SM > The Easternmost Isle > > _______________________________________________ > Sent via [email protected]. 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 [email protected]. 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 [email protected]. 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
