A *quick* :-) question concerning setting circles on the ETX:

A friend has an ETX and is determined to use the circles! The manual says
to use the upper set of numbers for the S hemisphere and the lower for the
N, which is where we are. However he finds that they work in the opposite
sense, in that if you align the RA for the current object against the
registration mark on the base, when you move the scope to the next object
the scale moves in the wrong direction - if using the lower scale. Simple
pragmatic solution: use the other scale. However these things set you off
wondering ...

Looking at my LX200, the inner set (manual says S) increases clockwise, and
the outer set (manual says N) increases anticlockwise. When slewing by
hand, moving the scope west decreases the RA reading on the outer scale,
correctly. Using the RA manual control, the fork (and hence the vernier
registration mark) moves while the scale stays put relative to the drive
base. Comparing this to the ETX, the outer scale on the LX would seem to
correspond to the lower one on the ETX, which also increases anticlockwise.
However, when he moves his scope manually, the scale turns with the forks
and so moves relative to the mark on the drive base. On both scopes the
scale turns with the forks when driven by the RA motor.

It seems that either the manual is wrong, or there is a problem with his
scope, which seems less likely. Any ETX, or better still, ETX + LX owners
care to comment?

BTW, he asked the dealer, who said "why would you want to use the setting
circles?" <ROFL>

Nigel
054d27m N 001d09m W

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