>Can someone provide a synopsis and report or opinion as to of and
>how this issue was or was not resolved?


If some lx200's (not all) are given the "FIELD" command from the object
library menu AND the current database is set to NGC (not IC or UGC) AND
the lx200 has a current RA setting between about 23hr19min and 0hr0min,
then the lx200 CPU freezes up in a non-functional state, with the keypad
totally unresponsive. Depending on the exact lx200 being tested and the
exact RA and random elements too, the motors will be left in one of several
different states after the freeze: 1-tracking normally at sidereal rate,
2-slewing one way or the other at any slew speed, 3-oscillating wildly with
the ammeter pegged. This occurs at least in altaz mode, I don't know about
polar, but I think so. Rebooting the scope returns it to normal functioning,
although sometimes the site coordinates and align mode setting (and time
and GMT offsets??) are trashed after the CPU freeze.

Relatively few scopes behave that way, apparently. The essential difference
between scopes that do and scopes that do not are not known. It also appears
that some scopes suffer a CPU crash without needing the "FIELD" command,
simply by being aimed at an object in the RA region mentioned above.

This was at one time blamed on ACP (by me!), but it turned out that ACP
was simply providing the set of commands that my particular lx200's computer
can not deal with (mainly, ACP repeatedly polled with the FIELD query, a
command that I have hardly ever used manually. Bob Denny devised a
modified ACP that allows switching FIELD polling off so those of us who
have the problem can still use ACP, even in the Bermuda RA zone.

Apparently for most of the folks who have this problem (and it's a small number
of people, based on ACP beta testing results) the solution to the problem is to
not execute a "FIELD" command anywhere in the region of RA mentioned above.

This is my own recollection of the thread; corrections or additions are welcome.

Rob Preston
Pgh PA

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