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Subject: [M]: "GOTO the Sun" procedure revisited
From: Mark Taylor
Reply To: mapug@shore.net
Date: Mon Aug 04 14:48:34 1997
I've been off of the Meade list for a while, and was unaware of the recent
discussion about the "GOTO the sun" procedure.
By strange coincidence, I was out this past weekend actively trying to
make it work for myself, only to get home and find that a friend had
forwarded an excerpt of the MAPUG thread to me in case I had not been
following it!
I had given it a try on the 3rd quarter Friday last week and couldn't get
it working. I assumed it was my memory, so I verified the procedure and
tried again this past weekend. It no longer seemed to be working for me.
I debugged the problem for a while and, unfortunately, I don't think
the procedure ever worked at all -- it was just a coincidence in the
time of year in which it was "discovered" :-(
This is what I found...
* The most-recently-used GOTO target (whether a catalog id or manual
coordinates) remains in memory until it is overwritten by the entry
of a new, valid target. (i.e. the last good GOTO can be reacquired
without data entry even after making multiple bad GOTO attempts.)
* By default, the "GOTO register" is filled with zeros at power-up. If
you do not enter any good coordinates, or if you only enter bad ones
(including bad catalog ids), the last value remains unchanged. (Zeros)
* The "GOTO Sun" procedure then distills down to this: Boot up the scope
(which puts zeros in the GOTO register); Enter an invalid GOTO target
(which is ignored, leaving Zeros in the GOTO register); GOTO whatever
is in the register (still Zeros). The procedure would likely work
without ever entering "star 900" or anything else!
Apparently, when the GOTO procedure was "discovered and verified" last
year, it was just serendipity; the sun was near to ra=0/dec=0 at the time
we were testing it.
The bottom line is that there is still apparently no shortcut to the Sun
other than doing a zero-star alignment followed by the sequence of
MODE(until you get the Ra/Dec display) -> GOTO -> (coordinates) -> ENTER
Although not a difficult procedure, you have to *know* the Sun's current
coordinates to GOTO it. Bummer. But at least you still have something to
synch on when you get there.
Regards,
Mark
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