[aprssig] Satellite positions: FREQUENCY

Greg Dolkas ko6th.greg at gmail.com
Wed Oct 19 23:20:11 CDT 2011

Hi Lynn,

More, below...

On Wed, Oct 19, 2011 at 4:23 AM, Lynn W. Deffenbaugh (Mr) <
ldeffenb at homeside.to> wrote:

>> Anything more than an hour away will have to get converted to a specific
>> time anyway, and written down, otherwise it will get forgotten or
>> mis-remembered.
> Then just query again when you think you've got the time.  Remember, this
> is for CASUAL satellite pursuit. (3 hours from now, I'll not be anywhere
> near the radio).  If you mis-remember a future pass time, oh well.  If you
> happen to recall it later (didn't that say somewhere around NOW), send
> another query.

I still very much prefer a specific time for anything that's more than an
hour from now.  Casual operating is even more dependent on ease of use, and
a specific time is easier for me.

>  I'm not sure how it would fit, but knowing the date as well as the time
>> would be good, given that a suggested near-GEO satellite could have passes
>> lasting more than a day, and not repeating for more than a day.
> Delta times remain short.  They reference NOW and the whole service is
> intended to be immediate, not future.  Why do people text so much?  They
> like the immediate feedback.  Yes, serious satellite workers plan hours
> (days?  weeks?) into the future to catch that "perfect" pass.  This isn't
> intended for them.  It's intended for quick pertinent information for NOW
> and hints into the future.

The inclusion of the date along with the time is not so important now,
because of the sorts of sats we currently have up there.  Mostly the
suggestion is preparing for the future, though even now it's a help in
reducing confusion.

>  Hmmm, LOS in 507min is kind of meaningless too.  Maybe LOS in 8h27m if
>> it's longer than an hour away?
> Expect the delta time format to transform when I have a moment (or maybe
> 6m29s) available.   That's a suggestion I can agree with.

:-)  Again, resolution to Seconds is not generally important or useful.  I'd
rather have a clearer message than a more precise one.  Casual operating is
best when it's easy to comprehend.

>> Don't forget about the max elevation for the pass.
> It's already there.  You haven't queried recently, have you?

Just tried it again.  Thanks!

>  ...especially if the Az of that max elevation is also given.  "10 degree
>> pass behind that big hill over there to the East..."  Yeah, skip it.
> Considering the azimuth along with the MaxEl for future passes and possibly
> a heading (4 or 8 compass points in characters) within a pass.  I'm finally
> hearing the INFORMATION that would be useful instead of PRESENTATION
> critiques.

8 points is usable, though a real Az is more consistent (El is in degrees
too).  4 points is a little too blunt.  And, Bob has a good suggestion too,
to indicate whether the pass is North or South headed.  Depending on where
you live, some satellites (ISS notably) are pretty deterministic in the
shape of their passes, but the general case is useful.  The polar orbit sats
can go N->S or S->N and have the same MaxEL and AZ.  You need to remember
whether they're an AM or PM North-heading bird, and what time it is, and now
you're having to think too much.

One last comment on the PRESENTATION thing.  It's important, once the basics
are in place, because that's what sets the really great and usable
applications apart from the not-so great.  I switched to APRSIS from Xastir
for my 24x7 iGate in no small part because of that.  Bob is the genius for
making insanely creative things out of bits and pieces one would never have
thought to use in that way, but he often has to resort to nearly
incomprehensible display methods for his input and/or output.  (Not his
fault, sometimes the bits just don't exist.)  Your gift is to take the
complicated stuff and make it easy to use, and "just work".  Don't give up
on us now.

>> I like the idea of asking what satellites are coming up next, but prefer
>> that to be the default if the message is empty.  Otherwise, the message
>> would have a command and a satellite name, say "PASS satellite,
>> satellite...", leaving open other commands, perhaps for MODE, FREQ, or other
>> things that can be predicted based on the satellite, time of day, and your
>> location.
> Non-satellite-directed queries (SATS or SATSRV) are further out in the
> future, maybe 7d13h or so... (but that's just a delta estimate).

> Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32
Greg  KO6TH
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.tapr.org/pipermail/aprssig/attachments/20111019/e2b7d0cf/attachment.html>

More information about the aprssig mailing list