It's been a long time since there was anything on this list, largely
because there is a LOT in common between LTM-1 and the legacy side of
Golf-TEE. But things are warming up, so here is a quick status report,
partly to remind you that LTM-1 is still in play and partly to remind you
that many of the Golf projects you are working on have another destination
and deadline as well.
First regarding "customers". AMSAT has signed a letter of agreement with
The University of Maine (Eric Skoog's alma mater, and the state university
of my home state) to provide an LTM-1 for their MESAT. They recently told
us that they have been assigned to a launch with a delivery deadline for
the completed satellite early next year. Obviously, this puts some
additional pressure on us, since they will need flatsat-level hardware
shortly. There is also at least one additional potential customer waiting
for us.
CURRENT STATUS
As you no doubt recall, the LTM-1 consists of three boards: The RxTx, the
ICR, and the LIHU. All of these are nearly identical to what we will use
on Golf-TEE (the LIHU can be one rev earlier, but probably will not be for
flight). In addition, there is software for the LIHU and customers will
expect documentation. Here is where we are on these pieces:
LIHU: We have two of the latest rev LIHUs populated and undergoing
testing. There will be another rev for a Golf-only function, but the
existing design should work for LTM-1 unless the testing finds design
problems.
RxTx: There is a new design that replaces Husky/1E obsolete parts, has
more and switchable RF power, and which we intend to test far more
thoroughly in an attempt to reduce the risk of HuskySat-type issues. (We
don't yet know if the RxTx is related to 1E's issues). Two of these boards
are under construction and Eric and I are anxiously awaiting one while the
other will undergo thermal testing.
ICR: There are no functional changes on the ICR compared to Husky and 1E,
so existing ICRs can be used for bench testing. However, an updated design
is required to replace obsolete components. This is in work.
Software: The software for LTM-1 will be a branch off the Golf-TEE
software with the RTIHU coordination code removed and with a more
generalized telemetry collection scheme and downlink format. As the
software person, I have avoided splitting off the new branch to reduce the
amount of merging required as bug fixes are made (and minor features added)
to the Golf-TEE code. That will include testing the support for the new
RxTx and the new LIHU.
Documentation: We will need thorough documentation (schematic, BOMs,
gerbers, masks, etc etc for hardware, functional specs for software) for
our customers and also because we will likely have the flight units
commercially built. I assume the documentation has been done for devices
that are in build, but we will want that documentation in SVN or Redmine
soon.
A fair bit of software documentation is in Redmine for Golf-TEE but more is
required . It will be written as part of the design for what software gets
changed as we split off from the Golf-TEE branch. My current thought is to
use UMe as reviewers for some of this since they are our first guinea pigs
(HuskySat uses the same basic software as LTM-1 and Golf-TEE, but much of
the intercommunication with their satellite was custom designed).
Continued thanks to everyone involved for all the work you are doing!
73,
Burns Fisher, WB1FJ
*AMSAT(R) Flight Software*
*LTM-1 Engineering Contact and Annoyer-in-chief* (Jerry feel free to give
me a better title!)