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Subject: (SBIGUSER) [Q]: Autoguiding and the LX200
From: Robert Fields
Reply To: mapug@shore.net
Date: Mon Nov 20 22:35:42 1995

I'm having a heck of a time with the DEC-axis and ST7 autoguiding on the
LX200.

I do understand that a tangent arm would be more accurate than the worm
gear, and that Meade has made tremendous efforts to provide utilities to
help the LX200 DEC be responsive enough for guiding. But, I just can't
get it to work well enough to allow autoguiding.

It seems as though the backlash correction value that gives me movement
with no jump changes every time I slew the scope. If I keep it perfectly
balanced I get the star going the wrong way before going the right way
(this actually occurs with both DEC motors - I thought I had fixed it
with the one I cannabilized from my other LX200). If it's out of balance
a little then moving the scope changes the whole backlash correction
picture. Sometimes I'll get a jump in one direction and not the other.
Very rarely I'll get nice smooth, responsive movement in both directions.
Then if I move the scope, everything changes.

When engaging the DEC with the ST7 doing tracking, every shot is ruined by
the DEC axis.

So here is my question:

If you have used an LX200 in Equatorial mode along with either an ST4 or
ST7 can you explain how you got it all to work properly ?

Many thanks in advance !

-Robert