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Re ao40 awol again & Access to AO40 at mid orbit

Dave in NH said:

>For the moment I will give the controllers the benefit of the doubt that
>they are really too busy trying to keep control of the bird and
>subsequently they don't have time to keep the general public informed of
>the changes they are making to the operating schedule. Allthough for the
>new and inexperienced users this can cause much frustration and confusion
>as many will suspect it is their equipment which is malfunctioning

I hope that you will continue to give us the benefit of your doubt beyond 
the moment!  :-)
AO-40 is a complex machine.  Just keeping track of its functions is an 
almost full time job.  Changes to the schedule are ALWAYS posted on the 
N-blk of the telemetry.  In fact, I always change the N-blk before changing 
the schedule.  These changes get captured and updated on the amsat-dl site, 
Paul Willmott's telemetry archive, and other sites.  With RARE exception I 
post these changes to the amsat-bb at or prior to their 
invocation.  However, last night's minor change, moving the eclipse window 
from MA 30/76 to MA 36/80 did not get posted.  We have frequent 
thunderstorm threats in my area and after the $8k damage this spring, I 
take everything off line, including the computers, e-mail, etc whenever 
conditions are menacing... so it didn't get posted until this morning.

Usually when I make an "update" post to the amsat-bb it evokes a small 
series of e-mail questions directed to me, some of which I, unfortunately, 
just don't have the time to answer, especially if I believe the answer is 
readily available elsewhere.  I sincerely regret this. I'm a teacher, in 
large part, by trade and I wish I had time to answer each and every 
question that arises.  Instead I have to depend on others on the bulletin 
board to help out newcomers.  I also work with Steve Fraser to keep his 
AO-40 FAQ as up to date and complete as possible.


<comments on separate e-mail questions>

>Several wrote and said that the transponder is now on continuously now from
>MA80 to MA216 with no gap, in spite of the implied one from the
>"OFF@=Variable" appearing in the schedule. The implication is that this
>note is an "artifact" from when RUDAK was active and had just not been
>removed from the schedule.

It's a "place holder".
RUDAK is off until further notice, but this line is left in the schedule to 
remind the command team of RUDAK's schedule line number, etc.
If RUDAK were active, the word "OFF" would be replaced with an MA value, 
and I would post the days of the week that it was scheduled to be active on 
the amsat-bb.  The "variable" never was meant to refer to variable MA, it 
referred to variable days of the week.  The MA was only occasionally 
changed.  OFF means off for now.

>To further confuse me however this morning I
>observed the following; at around MA143 I was hearing the MB a good 3-4 S
>units above the noise. The tracking program I use (WinOrbit) said the Squit
>was only 5 degrees yet I was unable to access the satellite even with 150
>Watts and a 15 element yagi. I also heard no other stations on the bird. I
>infer from this one of two things; (1) Either the transponders are in fact
>turned off at MA143 (beginning at MA @ when ever that was)..... OR
>(2)WinOrbit is incorrectly reporting the squint and no one (including
>myself) can get in because the Squint is really bad and WinOrbit didn't get
>the message.

The current ALON/ALAT ~ 34/0.  With those values, although I don't know 
your exact lat/lon, I'm sure the squint was considerably higher, more like 
30 degs. The beacon is much louder than a passband signal and at 30 degs 
squint most users (except some CW ops) wait for things to improve.  With 
some older software programs, the squint will not read properly unless the 
ALON has 180 degs added or subtracted (whichever give a value between 0 and 
360) and the ALAT has a sign change.

Conditions are extremely good now late in the orbit when the squints are 
low and the range is not nearly as far as at apogee.  I understand your 
frustration in grappling with the complexities of AO-40.  However, if you 
stick with it, things will become clear and you will be rewarded with 
armchair DX throughout the hemisphere of visibility.


  Stacey E. Mills, W4SM    WWW:    http://www.cstone.net/~w4sm/ham1.html
   Charlottesville, VA     PGP key: http://www.cstone.net/~w4sm/key

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