Because of the low orbits of these satellites, operators have only about a dozen minutes (usually less) to make "contacts" (i.e. exchange callsigns and grid squares). You don't have a conversation. If you are one of those hams that loves collecting minutiae that 99.95% of the world considers to be about as impressive as owning the complete set of Burger King Star Wars cups, then collecting grid squares from satellite contacts is really, really cool. For me, working FM satellites is done because it's a skill, although not a particularly useful one, and because it involves low power and simple gear.
Phase 3 is High Earth Orbit (HEO) and elliptical orbits that allow for longer passes. In the case of elliptical orbits, the downside of longer passes is long periods when the satellite isn't available. We don't have any of these satellites up yet, though one has been sitting around for a while waiting for a launch. HEO operation involves much more specialised equipment to receive the signal from much further away, and also more power. While VHF/UHF will be available (supposedly) on Phase 3 "birds", the emphasis seems to be more on 1.2 GHz -- and also on digital modes instead of analogue voice.
I'm sceptical that multitudes of amateurs will buy specialised gear that connects to computers for Phase 3 operation. Things are just spread too thin as it is. And "old school" hams will certainly rail against it, as it undermines their firm belief that simply everyone is absolutely dying to get on HF and communicate over long distances. On the other hand, for less than the cost of an HF rig and antenna, Technicians could reliably work large areas of the globe out of an apartment -- or any other antenna-restricted environment. It would really come down to the human element, as so much of amateur radio does in the age of the internet and smart-phones. If Phase 3 is predominantly text, and/or largely about "making contacts" (as opposed to actual communication), then it will probably remain a small niche that a few experiment with for the novelty and soon abandon.
Underlying all of this is a situation where a handful of hams are calling the shots for the future of satcom. These are people who donate heavily to AMSAT, on the order of thousands, and they have an out-sized voice in how Phase 3 and Phase 4 will take shape. And it's an extremely geeky "voice", as well. Looking at the plans and visions of P3/P4, it's clear that the focus is all about potential and very little about fulfilling the desires of most operators. I don't hear much of a clamour for an "internet in the sky" data network over amateur satellite, but that's what the people who contribute to AMSAT are dreaming about. It's less about a filling a need than it is about proving a concept. The average bozo will be allowed to use this actualised concept, but it doesn't really matter if they do or not. The criteria for "success" of these projects has very little to do with the extent that they are actually used by amateur operators. There are vague mumblings of emergency uses (EmComm), as are found in virtually every aspect of the hobby, and glowing promises of the potential to communicate over long distances and from remote areas. The question of who will actually be using these satellites, however, is completely ignored.
Not to go too far afield here, but this touches on one of the weirdest things that I find in amateur radio: the idea that "contacts" somehow mysteriously materialise to the deserving souls that spend the money and do things "right". There's another human being on the other side of that QSO, folks. The whole thing pretty much falls down flat without them. Activity is not some kind of impersonal, elemental quality like the weather. Many a repeater has been put up and sits dead based on the "build it and they will come" concept.
To me, it seems that Phase 3 is a "build it and they will come" type of project. Of course, if a mere hundred (out of several hundred thousand operators in the U.S. alone) operators use it, the usual propagandists will declare it a wild success. And, as long as only a relative few are footing the bill for this toy, it doesn't really matter.
It's harder to make this case for Phase 4. While the plans are still quite vague,there are some details.
First, is a geosynchronous orbit. The satellite will be in the same place (as seen from the ground), rather than pass over. This also means that the P4 sat would be there 24 hours a day and allow actual conversation.
A geosynchronous orbit has the same period as the Earth's rotation—just under 24 hours. A satellite in such an orbit is easy to locate and access. In this case, the satellite will always be within a band of longitudes over the Americas, continually accessible to any amateur radio operator there, including the students and researchers at the Virginia Tech Ground Station.This is similar to satellite TV or XM/Sirius radio. You point the antenna once. This means no tracking with a handheld beam, or using a motorised dish for Phase 3 operation. The idea is that Dish TV and Direct TV dishes could even be used, making amateur radio accessible to virtually anyone in condos, town-homes, apartments and rental housing in general. You're no longer tied to your local repeater, and you don't need EchoLink to access other repeaters. You could operate from your RV without stringing up a long dipole, for example. Maritime use is possible. The downside of this is that you are tied to the same geographical area for coverage. Europe and Asia wouldn't be accessible, nor would Africa and Australia. It sounds as if Canada down to Uruguay would all be connected -- though the closer you get to either pole, the more challenging it would be to get a decent view of the horizon.
Second, the P4 satellite would use a 10 GHz downlink and a 5 GHz uplink. So we aren't talking about using your dual-band HT any more. These frequencies are completely line-of-sight, obviously. However, you're operating line-of-sight into the sky. You can use less power at these high frequencies, more directionally, and there's more bandwidth available than we could ever dream of on 2M/70cm. The downside is that feed-line losses are insane in these bands. Much of the RX/TX hardware would have to be located on the dish itself, with only a baseband signal running to the actual "rig".
Using SDR technology, the minds behind this project have set a "target price" for a station at $1000. That's more of a wish than it is a firm figure, though. Everything will be open source, so the market is open to experimenters to sell radios for niche applications and also for "bare bones" rigs. The downside is that, without proprietary rights, the YaeComWood manufacturers will most likely be uninterested in developing products for the P4 satellite market. This leaves a lot of engineering and design talent off the board. On the other hand, it creates a big market for Chinese manufacturers at a time when VHF/UHF FM is saturated. For the first few years (at least), I'd expect users of the P4 sat to be few in number and almost entirely geeks discussing their radios. It would be a big investment for new hams, and probably force a choice between HF and P4 sat operation. This means that the hysteria and fear-mongering by the 'experienced' hams will make The Great BaoFeng Hysteria look tame by comparison. There will be few Wise Mentors to ease Technicians into P4 operation, and a lot of effort and 'advice' (i.e. snarling brow-beating) to pursue your General and HF operation instead. Even though P4 will use RF (as opposed to EchoLink), convoluted and irrational arguments as to how P4 satcom isn't "real ham radio" will be common -- and loudly expressed.
Third, gateways are envisioned. This sounds very much like a repeater. For example, a local repeater would be connected to a "ground station" (one of those $1000+ rigs), and operators could access the satellite (or at least certain applications) using rigs that they already have. This has huge potential to shake up repeater operation. While most local two-metre repeater owners would likely shun the concept, it would make mobile operation of a P4 sat possible. It could also undermine the growth of digital modes (such as D-Star and DMR) that rely on networked operation for their appeal. There's an opportunity for these modes, however, to expand by providing access to parts of the world that the P4 satellite wouldn't reach. The digital mode that allows access to a P4 ground station would become the superior alternative almost overnight. Imagine System Fusion users in Japan or Australia, for example, having linked access to such a satellite through a North American ground station. If Yaesu had any brains, they'd set up such a station out of their own pocket just to sell radios and gain market dominance.
Fourth, it won't just be FM. Since a variety of modes are envisioned, other ground stations might be gateways for text modes using the internet. APRS gateways could be linked without the internet, though the cost of this would probably be prohibitive. Still, it would allow APRS messaging to be sent using RF over two continents, as well as any other WinLink applications such as email or BBS. The P4 sat would use:
many different experimentation and communications opportunities ranging from simple texting to voice, streaming video, data exchange, and reliable EMCOMM access in remote areas, with bandwidths to support many satellites and users.Of course, EmComm figures largely in the 'sell', though I see a less compelling case for it. You're going to have a $1000+ radio and a dish, plus a battery and solar panels out in a "remote area" that VHF/UHF repeater or simplex operation isn't suitable to cover? Do I really need to talk to someone in Chile if a disaster strikes a major metropolitan area or if I'm searching for a lost hiker in Utah? I'm sure that are a few highly specialised instances where this would be somewhat useful, but QRP CW with an NVIS antenna would make an equally strong case (and be more portable, probably). Streaming video might be useful in disasters, I suppose. I doubt that gateways will be set up to handle streaming video using repeaters, however.
Overall, there's a lot of potential. If prices for ground stations with more limited applications come down to the $500 range, P4 satcom could easily be as popular as HF. It would also be in the range where clubs might add a ground station to repeaters, even if it only would be activated for specific hours. The major issues would be what kind of people would be attracted, as well as managing the load. With only five time zones covered, activity is going to be concentrated in about a twelve-hour period, with the rest of the time being mostly empty. If activity is little more than geeks talking about their radios, or brief 'contacts' instead of conversations, it would be hard for many to justify getting into P4 satcom. And, as previously mentioned, P4 operation will be roundly derided and vehemently criticised by the "Old Guard". Nothing scares the 'experienced' hams more than change does. On top of that, their knowledge won't be particularly relevant to SHF electronics or SDR. On more than one level, the 'experienced' ham will be a "newbie" to this sort of thing. Expect a whole lot of bitter whinging about how "ham radio has changed", and vows to sell their gear from the old-timers. Oh, well.
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