The runaway RA had become runaway DEC as well by the time I contacted Tom
Hoang at the Australia Desk. Tom was as unfailingly courtious and prompt as
ever and faxed an RGA after I explained the problem. I duly sripped the
electronics and drives out of the scope and sent them to Meade on 28
October, and on 18 November a replacement kit arrived. It contained (as
near as I can tell), someone else's reconditioned RA and DEC drives, my
original keypad, power panel and cords, and my circuit board with 2 new
L2724 dual power op amps soldered in.

The first problem occurred during reassembly of the electronics; the
circuit board did not seem to fit properly. Closer examination revealed
that the problem was due to the heat sink on one of the new L2724's. The
way it was formed the dust cover on the bottom of the scope could not sit
into it's recess properly , so that it was proud of the underside of the
alloy base. The weight of the scope was thus transferred to the heat sink
and the circuit board. Gentle pressure would not fix the heat sink problem;
the IC wuuld have needed to be unsoldered and the heat sink bent in a vyce
or similar
to fix it.

The second problem appeared when the power was switched on; the RA runaway
was fixed but the DEC still ran away. Wiggling the wires to the DEC drive
circuit board would reverse the runaway direction, cause the drive to
osillate from one direction to the other, and even stop the runaway. Not
permanently though.

So I contacted Tom on 24 November, after I was sure I had not made some
silly mistake in reassembly, explained the problems, and he said he would
talk to his people and let me know what they could do. He later rang back
and said they had agreed to send out by express courier a service kit
comprising brand new circuit board and new RA and DEC drives. I was asked
to return the faulty, repaired board and drives when the new kit arrived,
which only took 3 days. Unfortunately when I opened the circuit board
antistatic bag it was immediately obvious that one of the IC chips (U6) had
not been inserted properly; it was sticking out at an angle and the pins on
one side were bent under it. This was a brand new circuit board! Anyway I
was able to remove the chip, straighten the pins and reinsert it, and the
board seems to work because with the new board and drives the scope has been
pointing and tracking like new.

I sent Tom a fax and told him of the problem with the new circuit board so
he could pass it on to th QA manager. He personally has been very good, so
full marks for customer interface. The problems I experienced could be just
bad luck and statistically insignificant, but it was certainly frustrating
for the customer involved.

----- Original Message -----
From: Geoff Todd
Sent: Saturday, 23 October, 1999 12:41 PM

> I had been having trouble with the RA drive on my 10 inch LX-200.
> Anticlockwise it was OK, but clockwise it was showing an intermittent
> problem, sometimes hesitating at the start of a slew, making shrill noises
> and sometimes slowing and speeding up. This has been going on for about a
> month, and I had tried to fix it by adjusting the position of the worm
> assembly wrt the wheel, with no success. The scope seemed to be working
> fine otherwise though, and tracking (in alt/az) was OK. This morning
though
> disaster; the RA started to run away clockwise when the power was switched
> on. I looked for obvious things like broken wires to the encoder etc but
> couldn't see anything. It occurs whether the keypad is plugged in or
not.
> So it looks like I will be able to report first hand on Meade customer
> service and support. Unfortunately Australia is a long way from
California.
>
> Geoff Todd
>
>
>
>
>
>

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