Jason,
I can easily imagine how you may have come to the conclusion by listening to some people on amsat-bb that satellites are becoming bigger, more complex and more expensive while not providing you with better services. You might even think that AMSAT officials are not listening. Nothing could be further from the truth.
P3E is designed to provide services similar to AO-13 in an effort to make it smaller, cheaper and simpler than AO-40. It also will carry experiments essential to the future P5A mission to Mars. This is a very reasonable increase in complexity for a good purpose.
Eagle is intended to be a series of satellites. Eagle has been designed to be smaller, lighter and cheaper than AO-40. Its shape was designed to optimize a low inclination orbit like the one AO-40 attained. This unintended orbit turned out to be very attractive to many users and it provides for orbit stability and much less propulsion, further reducing mission risk. It also carries fewer payloads and these payloads have been specifically chosen to get the best performance for the maximum number of users.
Both P3E and Eagle have chosen Software Defined Transponders (SDXs) to implement the "linear transponder" functions for many reasons. Among these are efficiency, stability, linearity, cost, in-flight performance improvement, the ability to simultaneously share the transponder with other modes (Packet, APRS, SMS are possible examples), and the ability to change performance parameters in flight. This choice does not make the satellite bigger, more expensive, or less useful, etc. In fact, it is just the opposite.
Eagle will carry a payload that it is hoped will revolutionize Amateur Satellite communications and Ham Radio as a whole. Initially called C-C Rider, I will call it the Advanced Communications Package (ACP) because it no longer uses C-band for both uplink and downlink. This package will be designed to bring satellites and DX to you and to many other Hams who have never been able to use a satellite or operate DX before. This is because the ground station antenna will be small, power levels reasonable, many modes will be supported (from Voice and CW to Video and data communications), the ground station will be affordable and the signal quality will be superior. Much of this is accomplished through the use of digital techniques so it will require all new equipment on the ground. AMSAT will design the ground station equipment and publish everything so you can buy it, copy it, sell it, or build it.
The Eagle band plan has been the subject of much discussion, of late. Eagle is still in the design phase and the band plan is not finalized, so don't worry just yet. The confusion was the result of the ACP (C-C Rider) team realizing that they had to find another band for the uplink. They chose S-band for some good reasons but that recommendation is under review by the whole Eagle team and is not yet final. There should be a final announcement at the AMSAT Symposium in a few weeks. I encourage everyone to come to the Symposium and meet your AMSAT officials and learn what is really happening in AMSAT.
There is much more I could say but, in summary, the new satellites are getting better in every way compared to the old ones. The future is bright and we need your support and involvement to achieve these goals.
Rick W2GPS AMSAT President Subject: [amsat-bb] Why do the amsats get more and more complex? From: Jason White jason@xxxxxxxxxxxxxxxx Date: Tue, 19 Sep 2006 10:48:44 -0400
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This is intended to be an honest question that I've wanted to ask, but I don't want to spark controversy or long threads that monopolize the reflector. I have a feeling this could go either way, so I'm just asking politely that the thread not go that way! It's not my intent.
Anyway, I'm just curious why it seems that every new satellite project proposed seems to be bigger and more complex than the last? I keep hearing about exotic modes and uplink/downlink bands for P3E. Software defined transceivers, etc. etc. and what it looks like to me are more and more failure points. I understand the need to push the limits of technology as a justification for our very existence, but personally I feel like the designs are overly complicated and highly priced. I'm not ready to switch my earth station to SDRs, for instance.. I'm dubious about putting one into orbit.. then again, I'm not skilled enough to make those sorts of decisions.
What I'm getting at is that Oscar 7 proved how reliable older technology can be.. For the price of one of the phase 3 birds it seems like several Mode B linear transponder sats could be put up, or a few more FM sats. I personally would much rather see a modest mode B sat in AO-40s intended orbital pattern than to try to wrangle parts for microwave.
Did it get too easy for people or something?
Wouldn't it be better to separate out some of the more experimental stuff from the old standbys? That way a failure of one whole sat would still leave something usable for the same money spent. My vote would be to piggyback a completely independent analog satellite onto P3E "just in case".
Like I said, please, I'm looking for a real, thought out response. I didn't write the above to be a critique or to troll or anything like that, I am just curious because it seems to me, as an outside observer, that after the failure of AO-40 the direction was to go bigger and even more complicated, which left me cold considering what I had done at my station to work AO-40. Even when AO-40 was up I felt it was very odd that time and money were spent on components and systems that were never used (did the solar panels ever deploy?) Yes, I know the sat was damaged, and that explains a good bit of it, but it still felt like some things were wasted. Emphasis on "felt".. I couldn't know the real process that resulted in the decisions made.
If someone could help me understand why the direction is the way it is maybe I could get excited about the bigger sats, but I think you get more "bang for the buck" with the smaller less complicated birds. My favorite so far is PCSat I. Mostly off the shelf hardware and I had a very easy time digipeating APRS through it. One of those in an elliptical orbit would be a hoot!
73s,
Jason - N1XBP
P.S. - One last plea, this isn't a troll! I'm worried people will think it is.
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