Weasner's 8" LX90-ACF Report #5

17 May 2008

8" LX90-ACF - The Wait Continues...

I am still waiting for a third LX90 (or for Bad LX90 #1 to be repaired). The second bad LX90 still has not been picked up (maybe I will get to keep it for spare parts...). Here's the timeline to date for this entire frustrating mess:

27 Dec 07 - Theft of my LXD75-8"SC discovered.
12 Jan 08 - Ordered a replacement LXD75-8"SC from OPT. It was on backorder.
01 Apr 08 - Cancelled the LXD75 order and ordered a 8" LX90-ACF.
07 Apr 08 - 8" LX90-ACF arrived. Skies were cloudy.
10 Apr 08 - 8" LX90-ACF "First Light". Serious vibrations discovered. Problem reported to OPT.
25 Apr 08 - Replacement 8" LX90-ACF received from Meade. Also had serious vibrations.
30 Apr 08 - UPS came to pickup Bad LX90 #1.
05 May 08 - Meade received Bad LX90 #1.

I continue to receive reports of other new LX90 telescopes with the same problem as well as feedback on the problems I've experienced. Here's some of the email:

Subject:	LX 90
Sent:	Thursday, May 1, 2008 13:41:40
From:	Jan H Kolst (koja@tele2.no)
I'm very sorry to read about the problems concerning your new LX 90. As
we say in Norway: "The third time is what counts". I'm not sure if you
have that proverb in US, but I'm hoping for the best regarding the third

Anyway I was lucky with my scope which I bought a year ago. I had the
PAT check at OPT and it is stilll working ok.Hopefully you'll have a
functional scope during this month.
Best wishes
Mike here: Yep, we have that saying. I expressed it to OPT just the other day!
Subject:	LX thumps ?
Sent:	Saturday, May 3, 2008 02:20:21
From:	Henrik van Holthoon (henrik.van.holthoon@wanadoo.fr)
Hi Mike now I am confused maybe I do not understand Thump I though you
where talking about vibration which could be oscillation but thump could
be drives are encountering heavy points in the drives which the drives
is trying to overcome causing thumps.

I hope your third LX will be flawless.

Have luck with your new instrument.

Regards Henrik
Mike here: The 3rd one had better be perfect!
Subject: LX90 problem
Sent: Saturday, 3 May 2008 2:14 PM

I was referred to your posting since I have experienced a very similar
problem on TWO brand new 8" LX90-ACF telescopes.  You can see my reports,
including several tests I did, at:


Reports #2, #3, and #4 discuss the problem.

I am now waiting for Meade to send a 3rd telescope!

Mike Weasner
Sent:	Sunday, May 4, 2008 15:30:47
From:	Todman Matthew (Matthew.Todman@comverse.com)
Many thanks Mike,

I've taken a look at your LX90 pages already. I ran through the test
spreadsheet that you compiled (alt only) and there appear to be some
similarities. The problem certainly becomes more pronounced at 0 & 180
deg (az) in fact at 180 degrees the knocking happens ~every 2-3 secs. At
90 & 270 degrees az the problem disappears.

One thing I did notice last night during further testing was that the
problem occurs more when I have my counter weight fitted. I'm using a
Meade 1209 microfocuser & JMI Motofocus which means that the scope is
VERY rear heavy. The counter weight weighs 1lb, 14oz and I need all of
that weight right at the front end of my OTA to balance horizontally.
Anyway, I'm going to get in touch with the main importer of Meade scopes
today (I live in Sydney, Australia) and see what they suggest.
Unfortunately, the scope is just out of warranty so shipping back to
Meade will cost ~$600 (ouch).

I look forward to see how you make out with Meade. Good luck with #3.


Matt Todman

Subject:	LX90 Vibrations
Sent:	Monday, May 5, 2008 00:01:02
From:	Robert Lashley (Robert.Lashley@Sun.COM)
Vibrations.  You're not alone.

I thought I was nuts or just too picky with the vibration problem in my
brand new LX90.  Or rather both of my brand new LX90s.

I also had ordered an LXD75 from my favorite east-coast photo dealer and
after a couple of months of "delayed shipments", I canceled the order
and went to OPT to buy an LX90.  I love OPT.  But I'm learning to hate

The first scope arrived and I set it up outside, did the usual
calibrations, put a dust cover on it, and waited for nightfall.  When
the first stars poked out, I did an alignment and then watched as
everything in the eyepiece bounced all over everywhere.  I immediately
realized that this was not a scope that could be used for AP, and I
doubted that any friend would ever get hooked on astronomy by me.

I did everything I could think of to stop it but ultimately called OPT
and asked for advice.  I described the vibration to them as an
occasional machine-gun rat-a-tat where the object in the eyepiece would
bounce around wildly.  They immediately asked me to let them arrange a
new OTA sent out from Meade.

Meade eventually sent a new one to me but without any communication
despite repeated requests for information about the process.  The new
OTA landed on my doorstep without warning (I discovered it there a day
later) and a week later a return shipping label was also left on my
doorstep without warning.  Both despite my repeated attempts to ask
Meade what was going on with the exchange.

I put the new OTA on the tripod and went through the usual calibrations
and alignments.  The vibration didn't show up as often but it was still
clearly there:  10 times in 30 seconds instead of the 1 per second of
the first OTA.  Additionally the normal motor action introduced a much
lower level of vibration in the eyepiece, but still a noticeable

I called Meade Tech Support this time.  They said that it indeed sounded
like a mechanical problem and asked me to let the mount track for an
extended period of time to see if the vibrations were reduced.

Following their advice, I put fresh Alkaline batteries in the holders,
tracked until they were drooping, then put a Celestron Tank (12v
battery) on it and let the scope "track" a phantom object nightly for
three nights. Then I took it to the back yard and looked again.

The constant vibration had pretty much ceased.  In my opinion, it
reached a tolerable level for AP.  But the 10x-in-30s rat-a-tat
vibration was still there.  And it is still unacceptable for AP work.

With the first OTA, I took the covers off of the motors and watched. 
Both axes exhibited the same symptoms but not at the same times.  The
motors occasionally seem to run free as if the optical encoder no longer
responds or doesn't send appropriate pulses, so whatever processor is
driving them would ramp up the motor drive looking for feedback.  I
originally thought this might be due to bad power which is why I
switched to the Celestron Power Tank and excessive in-line filtering to
make sure the power supply was unquestionable.  No change.

I received the first OTA in early April '08 and the replacement in late

I noted that both smell very strongly of car axle grease which is used
to lube the gears for both axes.  This was not the case when I bought my
first (yes, first) LX90 last fall.  It arrived with a broken (shattered)
tripod and the dealer that time insisted I send back the OTA along with
the tripod.  That OTA had none of these problems and didn't have car
grease in it either (I believe lithium grease was used back then but
Meade apparently needs to be even more profitable and lithium grease
must be expensive).


OPT has been a blessing so far.  But I'm trying to figure out how to
back out and become a Celestron or Orion customer now.  I've had more
than a lifetime of bad luck with Meade.

Please keep blogging about your experiences.  If you'd like, I'll keep
sharing mine with you - until we get usable OTAs out of Meade.



Today Meade told me to send this 2nd OTA back to them for repairs. 
They'll take 4-6 weeks to "fix it" and send it back to me.

I've dropped a note to Mike at OPT asking his advice on that:

- if I send it for repairs instead of a swap, I'm set back another 4-6
weeks in my quest to get a scope.

- if I insist on a swap, they'll most likely send me another OTA without
opening it up and checking it out - and the odds seem to be that it will
have the same problem that these others have had


This started last October when I tried to order an LX90 UHTC from a
different dealer. It arrived but the tripod was broken - in a way that
UPS could not have done.  After many miscommunications, the tripod and
the OTA ended up going back to the dealer and a lengthy refund process
started.  I finally got my credit card charges reversed in February and
placed the order for the LXD75 with a different dealer.  At the end of
March, this second dealer told me Meade was giving them a new shipping
date of sometime in May.  That's when I canceled the LXD75 and went to
OPT to try for the LX90 again.  It's amazing that Meade is still in
business - especially when you read the usual exchanges in the yahoo
groups about them.

Good luck to you.


And more:

Sent:	Thursday, May 15, 2008 07:41:47
Any progress on yours?

I was waiting for advice from the OPT guys on Meade's last offer to
repair my scope. My concerns are that it takes up to six weeks to turn
around the repair, i.e. six more weeks of waiting for a working scope to

- do I go with the wait, resting assured that the scope will actually
work the way it was designed to when I get it back?

- do I ask for a swap in transit for immediate satisfaction - but get
yet another un-opened box from the factory that most likely also
exhibits the same vibration problem?

I'm thinking of going with the repair route. I already have the shipping
tags and RGA number from Meade.

In the meantime, I've tried a few things to see if I can reduce the
vibration, but without avail.  And I shot the worst looking AP photos
I've ever seen.  This expensive scope has got to be fixed.



Oh, and one more important note:

when I loaded up the OTA with my Canon 20D and adaptors, the vibration
and noise increased drastically.

I did not attempt to counterbalance the camera.  The OTA didn't move out
of alignment with the additional weight.  I have a piggyback bracket but
this was for prime AP, so the camera stuck out much further.

And I'm remembering that the OTA is not well-balanced by itself. Still,
I would expect Meade to deliver a functional mount with the
out-of-balance OTA regardless of using counterweights.

But it left me wondering if a perfect balance on the OTA would reduce or
eliminate the vibration.

(I'd hate to get stuck with having to make the balance perfect all of
the time.  I change eyepieces that have different weights - like my
zooms, etc.)

Mike here: I'm still waiting for #3 or a repair of #1. I have OPT checking on the status since I don't have any tracking info with Meade. I did notice quite a bit of rearward heaviness with all the standard accessories attached. But without any attached the OTA was front heavy. So I suspect Meade has made an attempt to balance things. I plan to do some more checking on balance when I get #3 (or repaired #1). #2 is boxed up for return.
Subject:	another thumping LX90... but this one was fixed...
Sent:	Friday, May 9, 2008 07:58:26
From:	richard seymour (rseymour@wolfenet.com)
From the LX90 group:
I picked up my LX90 from Bintel in Sydney today and I'm happy to say
that it seems to have been fixed. I've just finished a 3 hour imaging
session and there was no sign of the rattling / knocking sound (or
corresponding image shake).
According to Don at Bintel, the problem was resolved by replacing the
declination motor / gearbox assembly. It had developed a fault most
probably as a result of the large declination / alt worm gear being
off centre with the worm drive. Instead of the worm gear sitting
exactly on the top, centre of the worm drive, it was slightly off
centre (towards the centre of the form arms). This also was resolved
by inserting a couple of washers behind the dec gear mount.

(BinTel is in Australia)

good luck (3rd time's a charm, right?)
Mike here: Thanks Dick. That might be the problem. I didn't notice any obvious offset when I had the plate off. And I had the problem on the RA axis as well. I'm still waiting for #3 to arrive and #2 to be picked up. I wonder if Meade is repairing #1...
Subject:	miserable company....
Sent:	Wednesday, May 14, 2008 22:52:09
From:	richard seymour (rseymour@wolfenet.com)
Further examples of "you're not alone" in the ticking LX90 game:


have fun

Stay tuned...

Go to the LX90-ACF Table of Contents.

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Copyright ©2008 Michael L. Weasner / mweasner@mac.com
URL = http://www.weasner.com/lx90/waiting.html