Looks like option 3 would work [2m monoband for school contacts] with the eventual 28, 145, 430 and 2400 MHz options planned for installation. That will provide 4 bands for 4 different modes.
I may be nitpicking your words, but that particular phrasing still sounds like self-limiting mono-band operation, which not only limits to exactly 4 modes, but overlooks the fact that with the long lead time of systems on ISS, there are years of overlap between the design and eventual operations of some systems. Allowing for "monoband" operations on any of these other bands is simply multiplying the current coordination issues across 4 more bands and making them a roadblock to future independent growth and development which should have less dependence on daily immediate crew involvement for every mode. Not perpetuating the same problems to other bands. What I would like to see ARISS say is something along these lines:?
1) Monoband 2m operation exclusively for school contacts only. No other uplinks or downlinks or any other modes will be planned without consideration of the requirement for direct crew involvement of every operation and every mode change for operation on 2m.
2) 430 MHz as a dedicated downlink band (no uplinks) 3) 28 MHz and 1200 MHz as dedicated UPLINKs 4) 2400 MHz TBD.
Number 1 makes 2m a lost band for any other modes or experiments except for the indicated limitations and inherent unreliablity. But does preserve the status quo.
Number 2 and 3 combined give an unlimited number of future modes and systems than can operate independenly, without interferrence and without intense coordination. (not just 4). And more importantly can be planned and worked on the ground independently as well.
By dedicating at least one band to exclusive downlinks and another band for exclusive uplinks, ALL mutual system interferrences are avoided as well as any requirement for crew involvement. Plus, all future Amateur Radio Operations and equipment, and planning can work independently, in any sequence at any time, and be preempted, replaced, or whatever as independent systems. That is the only way to avoid the problems of mutual interference, intense crew involvement for every mode change, and intense coordination for daily operation.
Even thinking of perpetuating even a hint of future monoband operations on any of the other precious bands is very shortsighted, and builds in exactly the kind of intense crew involvement, intense coordination, and intense and detailed interleaved planning... All of which can be avoided by never even considiering any future monoband designs or operations.
Blocking any of these other bands with any future plans for monoband operations I fear is short sighted...
What we really need to see is for ARISS to commit to dedicated uplink and downlink bands and the prohibition of any monoband operations in those bands. Without that, then there is no clear independent path for any future missions, experiments or operations, which does not bring us back to the present situation of the potential for incompatible, conflicting, crew-involved , interrelated, cordination intense processes.
Or something along those lines...
Bob, WB4APR
-----Original Message----- From: sarex-bounces@AMSAT.Org [mailto:sarex-bounces@AMSAT.Org] On Behalf Of Robert Bruninga Sent: Wednesday, May 02, 2007 11:07 AM To: sarex@AMSAT.Org Subject: [sarex] Re: Future ISS amateur radio modes
Once the planned hardware is aboard and installed, having
each system
dedicated to a specific operation will minimize the need for
mode
changes and crew interaction.
But this can only be true if all systems operate with clear isolation of all uplinks from all downlinks on separate bands. It is impossible to have independent systems operating with
uplinks in
the same band which may be used for downlinks.
Until ARISS commits to a permanent dedicated downlink band
which then
guarantees other known bands for non-interfering uplink bands,
future
planning is stymied by crew-required mode changes and lack of independence of systems.
Current use of 2m for both uplink and downlink, prevents its use by any other system for any other purpose without crew intervention
on every
such use. There are really only three choices...
- make 2m the downlink band for simplicity of reception
around the
world. Even the least advantaged country should be able to at
least
borrow an ARISS UHF uplink radio for a school contact. But it does require Doppler tuning in the blind on the uplink. Tuning a radio +/10 KHz is not a hard skill to learn.
- Make UHF the downlink band so that recipients can simply
tune the
Doppler to best sound, and then uplink on 2m is fixed frequency with no problems. Less interference with UHF radars...
- Continue status-quo, and use 2m for both uplink and
downlink for
school contacts and either require crew intervention with
every mode
change for use of 2 meters for anything else, or require all
other
systems to not use 2m for anything, so they can be independent
of crew
issues.
Until there is a permanent commitment to one of these three possibilities, uplinks and downlinks can not be planned
without
conflicts, and crew intervention is required in every mode
change on
every system that might want to share 2m for anything.
Of 60+ amateur satellties, few (with more than one mode on board) use monoband operation. There is a good reason for
that.
Uplinks and downlinks are in different bands for operating independence of modes. Just what we need on ISS.
Just a thought. Bob Bruninga
Sent via sarex@amsat.org. Opinions expressed are those of the
author.
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Sent via sarex@amsat.org. Opinions expressed are those of the
author.
Not an AMSAT member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/sarex