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Falconsat status and general info




>I don't know if Falconsat has any amateur payloads, as the link is broken but
>I will fix it as soon as I get a good link.

Falconsat-1 does not have an Amateur payload.  It is on 'military' 
frequencies shared with Little LEO.  Down link is on 400.475 MHz (backup 
400.680 MHz) and will only be transmitting when in view of the Air Force 
Academy in Colorado Springs, Colorado, and only when being actively 
controlled by the cadet team.

The WEB page is being updated.  I'll publish the URL as soon as it is 
completed.

Following is not an official Air Force position.

Here is a status, and some general information about the process of getting 
new satellites working:
As near as we can tell Falconsat-1 hardware is working properly.  We are 
not getting as much power from the solar panels at this point in the 
commissioning activities as we anticipated.  As a result we are operating 
the transmitter only one pass a day (usually the best AM pass).  We do not 
believe there is a problem, just sun angles and eclipse periods that have 
conspired against us.

On separation from the JAWSAT MPA Falconat-1 turned on in a very low power 
'safe' mode by design.  Commissioning consists of slowly and carefully 
loading software into the on board computer, then using that software to 
turn on each component in the satellite and test it to see if it is 
operating properly.  In  the process everything is very carefully 
measured.  As usual with a small satellite, carefully managing the power 
situation is critical.  The last thing you want to do is run the battery 
down.  This resets the CPU, you loose all your uploaded software, and it is 
rather hard on the batteries.  So this process usually takes longer than 
anticipated and always longer than anyone would like.  Many satellites have 
software in ROM that executes on separation which includes some telemetry 
beacon capability.  Falconsat-1 does not, for a variety of reasons.  It is 
necessary to load software before we get the first telemetry.  It is sort 
of like giving birth, tickling the baby and hearing the first cry, but not 
getting any vital signs until you feed it for a few days.

(No doubt the initial checkout and commissioning of P3d will be much like 
this.  We will all want to use it the first day while it may take many days 
or weeks to commission.  The same process is typical of just about all 
satellite operations immediately post-launch.  They don't just pop off and 
start working.)

During these immediate post launch operations there always seems to be 
inadequate information to satisfy everyone who is excited about the 
prospect of hearing or using a new bird work.  Let me give you a satellite 
engineers perspective, Falconsat-1 specific, but generally 
applicable.  From about three hours prior to the launch, through the 
launch, and through the 10PM news cast time, the ground station at the AFA 
was overrun with visitors, well wishers, officials and media.  Two TV 
stations did multiple spots, including live shots and interviews with 
various people.  During this period the cadet operations team continued to 
practice commissioning procedures on the simulator.  About 11PM the place 
cleared out and most folks went to get some sleep.  A small crew stayed up 
all night getting reports from the launch team on separation success, 
rocket telemetry, updates on orbital elements, etc.  Naturally a snow storm 
blanketed the area making the roads a mess.
The first pass was at 0352 the next morning.  Adrenalin was running 
high.  The keps were pretty close, and there was a round of applause as the 
satellite responded to the first request for a beacon frame.
Several steps were performed to test the RF components and links.  We 
transmitted to both receivers and verified they received good bits and were 
on the correct frequency.  We recorded signal strength using s-meter 
software and pictures of the spectrum analyzer.  We measured and 
photographed the eye pattern to characterize transmitter linearity.  We 
measured the bandwidth of the transmitted signal and attempted to get a 
feel for spin rate from down link fades.  We checked the circularity and 
sense of the down link signal.  We checked for spurious CPU resets.  We 
then started uploading software, which continued through LOS.  AOS and LOS 
times were recorded and compared to the terrane masking map and keps.  We 
were already trying to sort out which object was really Falconsat-1.
After a 10 second break to toast with non-alcoholic bubbly, we immediately 
began analyzing the data, doing a postmortem on the written procedures and 
planning for the next pass.  Cadet teams were debriefed.  Brief status 
reports were written for senior officers.  Contact was made with some 
sponsors to give them reports and thanks.  The launch team officials were 
contacted and thanked.  At some point we stuffed down cold pizza.

The 80 minutes between passes whet by quickly.  Next pass things went a 
little slower; uploading software was a bit less successful.  Much time was 
spent trying to trouble shoot that problem.  Logs were consulted to see 
what was changed between passes.  The other up link was tried.  Various 
power levels were attempted.  We locked on the transmitter to see if it was 
a TXD problem (and proceeded to make the power amp smell real bad).  It got 
a bit exciting, especially with an audience.
Subsequent passes went much like that second one (without the bad 
smell).  Passes occur between 4AM and 7AM local, and again between those 
hours in the PM.  Most of us got a couple of hours sleep for the first 
three nights.  It catches up with you.  Cots in the back of the lab were 
well utilized.  We quickly learned that when someone orders 20 pizzas you 
better get yours before the cadets get a shot at it.
On about every pass there has been something that needs analyzed.  That 
analysis and planning continues between passes.  It is easy to get caught 
up in the process of making this thing you spent two or more years on work 
right.  You are analyzing unknown situations with very very little 
data.  You are digging through testing records and logs because you can't 
remember for sure what the (insert just about anything) measurement was two 
years ago and you absolutely MUST get it perfectly accurate now.

So folks, patience please.  Give the guys and gals working on these birds 
an opportunity to concentrate on their job.  In the commercial satellite 
world some high paid PR group would be cranking out press releases and 
slick video clips.  In the Amateur and University world a hand full of 
folks do it all and they need to concentrate on their most important job.

Repeat, this is not in any way an official Air Force position.

Back to tweaking telemetry code and eating cold Chinese.

Jim White
jim@coloradosatellite.com
wd0e@amsat.org

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