Fellow MAPUGers,

This afternoon, I attempted to start my 8" LX200 to look at Sunspots
(with filter etc.) as I’d done many times before. The setup was LX200
in Alt-Az mode powered from a 12V battery via the #1218 transformer. I
also had a notebook computer and with it’s separate transformer hooked
to the same 12V battery. The notebook was connected to the LX200 via
the RS232 port, e.g. a setup I’ve used many times. The notebook was
however not yet powered up. When I switched ON the LX200, it
immediately started to run at full slew rate toward West, drawing about
300 to 400 mA as evidenced by the bar display on the control panel. I
immediately switched the LX200 to OFF and then tried again. Same
result. I then attempted to start the LX200 after reconnecting it to
the 120VAC transformer supply, same run-away condition on RA axis
occurred.

I then moved the LX200 inside and set it up on a table. I carefully
checked both the hand controller and DEC cables with an ohm-meter for
continuity, wiggling cables etc. Both appeared OK. A check of the CMOS
battery behind the LX200 control panel showed 3.02 volts. I did replace
it with another that read slightly higher, e.g. 3.12 volts. The fuse
was also OK. Additional attempts to start the LX200, using the 120VAC
supply, again resulted in either the run-away RA condition or most often
the hand controller simply blinked 3x then displayed Meade and simply
stayed in this totally unresponsive condition. One time, the system did
initialize correctly. I noticed that although the site location names
were still present (and also presumably the lat. and long. settings) the
clock date and time were very wrong. Time read 00:01:40 and date read
00:00:44. I reset same and the controller reported it was updating the
planetary calculations. This one time, the controller appeared to be
working OK in that the LX200 could be slewed in RA and DEC via the hand
controller. However subsequent restarts of the system again showed
either the runaway RA or totally unresponsive hand controller. Note,
these conditions occur even if both the hand controller and DEC cables
are disconnected from the control panel when it is switched to ON.

I’ve checked Doc G’s site and the archives. One reference to run-away
RA in West mentioned a problem with the encoder mask falling off.
Another reference with run-away RA in East mentioned a keypad problem.
A third reference to run-away RA mentions simply that the whole system
was returned to Meade for repair. I fear the latter is my recourse
unless some of the more knowledgeable people on this list have any
suggestions.

Thanks, Ron at 40N by 76W

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