[APML] ST-7XE autoguiding questions

["Roland Roberts" <roland@astrofoto.org>]

Last night I finally had clear weather to get out and try my "new"
(second-hand) ST-7XE.  I had already done what indoor tests I could do,
and the camera had seemed to be working fine (nice darks, cooling reported
it was working).  The ST-7XE has a CFW-8A "permanently" mounted on the
front.  That precludes the used of a camera lens adapter without removing
the CFW-8A, so I didn't take any test images (actually, I tried, but I
couldn't get focus; still it showed fuzzy blobs, so it appeared the camera
was working).  The scope is the Orion 120ST (120mm f/5).

I did a quick alignment of my GM-8 with the polar scope then a single pass
at a drift alignment using a 5X Powermate and a 12mm reticle eyepiece. The
polar scope is a bit too dim for Brooklyn skies; I couldn't see the second
star, but a third star was marginally visible at the correct spot.

I then pulled off the diagonal, mounted the ST-7XE and rebalanced.  My
goal was to take a few throw-away images, then get the autoguiding
working.  I was able to take a few short exposures and was happy.  But the
autoguiding does not appear to be working.  I didn't write down the
contents of the calibration screen, but it looked funny---the numbers were
all zero which suggested to me that it wasn't moving the mount.  Asking it
to autoguide afterwords showed that the star it selected was slowly
drifting away.

Okay, now for the questions.  I'm new with the equipment and reading the
manual I'm not clear on a few things and hope someone here can help me
out.

I have the older Gemini with the RJ-45 jack for autoguiding.  Do I need
the SBIG relay box *and* the Lacey optocoupler?  I plugged the optocoupler
into the autoguider port and the cable into the optocoupler.

Do I need the dual relay cable with the CFW-8A?  The DB9 connected coming
from the CFW-8A already has an RJ-45 on the rear, so I plugged the other
end of the autoguider cable into that.  If I do need the dual relay cable,
that might be my problem.

At one point, before activating the autoguiding, I plugged the cable
directly into the autoguider port.  I didn't activate the CFW-8A or any
autoguiding commands before I realized my error and put the optocoupler
in.  Am I likely to be okay or have I toasted something?

Thanks!

roland
--
                       PGP Key ID: 66 BC 3B CD
Roland B. Roberts, PhD                             RL Enterprises
roland@rlenter.com                            6818 Madeline Court
roland@astrofoto.org                           Brooklyn, NY 11220



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