ETX-105 FEEDBACK Last updated: 19 January 2004

Subject: Niall's Demon ETX
Date: 1/16/04, 12:32
From: Don Sutherland (don_sutherland@yahoo.ca)
Niall Saunders seems to have been cursed with the ETX from hell. The
fact that his scope has no hard stops on the Az axis is an indication
that something is SERIOUSLY wrong. Something is broken or missing
entirely. I doubt Meade would hesitate to give him a new scope for this
reason alone.

Niall mentioned that the black and blue (how fitting) wires to the Dec
drive are visibly damaged. In addition, the strands of wire inside the
insulation of the four wires to the Dec drive may be broken from
rotating the Az axis 3 turns each way, causing intermittent contacts and
alignment failures.

I do a lot of troubleshooting as a part of my job. If I can't find the
cause of a problem, it is usually because I have overlooked or ignored
something obvious. Niall's ETX has no hard stops. As a result, the
wiring to the Dec drive is damaged. This is a no brainer! Return Scope
to Meade for warranty replacement!

Regards,
 
Don Sutherland

From: Bruce
Hi Niall

I saw you problems on Mike Weasner's site. I have a '105, and some
comments might be in order. I presume you intend taking pictures (that's
why you are polar aligning the scope), and that you are using an
Autostar. If you don't plan to take pictures, don't bother with polar
alignment.

1. Hard stops on RA axis. My (early) ETX105 has them. I get about 3
turns, stop to stop. I have seen a reports of these being broken on
various models, so you do need to check this with Meade.... But don't
hold your breath. Try emailing engineer@meade.com - you might be lucky.

2. Home position.  The altaz home position is with the control panel
pointed to the west, and the tube level and pointed north. I don't know
what the home position is for polar mode (I've read it on Mike's site,
but haven't verified that it works.) In case it helps, home position for
the LX200 is with the scope pointed at the intersection of the meridian
and the celestial equator.

3. Alignment failed - this is caused by having the wrong angle (i.e.
segment of a great circle) between two alignment stars. The scope can't
work out where it is on the world, and gets confused.

4. As far as I know, the polar alignment routine only requires alignment
to Polaris (by adjusting the wedge) and sync on a single star with RA
~6h different from the RA of Polaris. It does not need two stars to work
- ergo I think your scope is trying to do an altaz alignment while
mounted on a wedge.

A polaris / single star alignment routine is pretty useless anyway,
since you frequently can't see through the eyepiece, and it's nowhere
near accurate enough for photography. I suggest you use the approach
offered by Bruce Johnson (see
http://members.aol.com/ccdastro/goto-tests.htm). I have tried this and
it works like a charm - I find it's as good as drift alignment and
_much_ quicker. (It was intended for the LX200, but the ideas will apply
to any goto-scope.)

5. MUF - this usually indicates bad power connections or low supply
voltage. Since you are running on an external supply, make sure that it
can source enough current - if it can't, the voltage will drop and you
could create a MUF problem. FWIW, I have an external supply that
produces regulated 12VDC @ 1 ampere, and this seems to be fine.

I have also seen an MUF failure when my ETX was significantly out of
balance, and when I had a dud Autostar cable. If you have a camera
mounted or are using 2" eyepieces, I suggest you balance the scope
carefully; since you're a computer person making another Autostar cable
should be a doddle - just check the order of the connections.

6. Easy align - I have had mixed experiences with easy align. One scope
I had to fix (LX90) wouldn't do it properly; otoh, mine does - I don't
know why. I recommend you use Paul Rodman's BestPair II to pick
alignment stars - http://www.ilanga.com/bestpair/index.shtml/index.html and do it
manually.

7. Finder - yes these are bloody awful, and a complete waste of money.
Perhaps you should bin yours and get a unity power finder. I use a
Telrad on my 12", and it's much more convenient than the finder,
although you might think of something a bit smaller for the ETX.

Hope this is a help

From: Niall Saunders (niall@njs101.com)
Many, many thanks for your kind thoughts and comments.

Yes, I AM trying to do digital astro-photography and, in any case, it
just seemed more 'natural' to run the scope in Polar-Mount mode, if only
because only one axis had to be driven. However, as my timed exposures
can only be 16 seconds maximum (for as long as I continue to use my
current camera) then perhaps the advantages of Polar mode are not really
worthwhile. After all, I can always 'rotate' any captured images as
required.

Currently, the dealer who sold the telescope last year (it is still
under warranty, purchased from f1cameras.com) has been FANTASTIC. He is
arranging for the entire scope to make a round trip to Meade - either
for repair, or replacement.

What I was really (originally) looking for, and everyone who has replied
seems to be confirming this, is whether (or not) the ETX-105 should have
had RA/Az hard-stops. After all, there must be other users that (like
us) depend on the huge amount of information exchange provided by Mike's
fantastic site. It appears that I ought to have end-stops, and I don't,
and the DEC/Alt feed cables have been badly damaged because of this. So,
others - BEWARE!!

Your comments on 'using' the scope are also very useful. Despite NOT
having hard-stops, I do NOT think that the damaged cables should be
causing the problems I noted the other night.

As far as Polar Home position is concerned - I have been setting the OTA
in the forks, such that the OTA is pointing AT Polaris (with whatever
'Kochab Clock' offset I can manage). This means that the OTA is
effectively 'aligned' with the forks, and I also make sure that the
forks themselves are 'parallel' with the ground. To me therefore, all
that is now needed for the scope to operate correctly, is for the
Autostar to move to a given RA/DEC coordinate, and the target SHOULD be
in the FOV. After all, the Autostar KNOWS the correct Lat/Long and Local
(UTC) time, and it KNOWS that it is currently pointed at the North
Celestial Pole. If I have been 'accurate' with the setup, then virtually
NO ALIGNMENT should thereafter be needed. If I did an Alignment in any
case, I would have hoped that the Autostar would have just been removing
any small errors 'left over'. But, when the first alignment star is not
even in the FOV of the FinderScope, it makes you wonder what is
happening!!

I need to spend MORE time trying to analyse what is happening - and this
is just eating up my viewing time. Hence the irritation. It is a shame
that Meade don't release some sort of 'flow chart' that might explain to
users what causes some of the problems to appear (MUF, Alignment
Failures, Proc Trap 2, etc.) I understand that the detailed code is
'intellectual property' - but 'bugs' (if they exist) could be ironed out
with constructive feedback from users.

I haven't looked at your two suggested links (yet!!) but will do so
later today/tonight. With a little luck, the roar of the rain outside
(reminding me of the Monsoon's first rain in Kenya, many years ago) will
eventually clear the air, and we might get a clear sky sometime soon!!
Then I can try things again. As I said, in the meantime I am trying to
hang on to the faulty scope for one more observing session, so that I
can try and identify what is causing my problems. That way others can
benefit, via Mike's site.

I am also going to look at powering the scope in a different manner -
just in case THAT has been part of the problem. Again, the internal
wiring does NOT inspire confidence. Even though current consumption is
low on these scopes (at MUCH less than 1000mA) I am not entirely
convinced that induced voltage drop (due to internal wires being too
thin) is NOT part of the problem. Why Meade went for a groove down the
side of the DEC/Alt mounting bolt, as opposed to a hole bored through
the same bolt is not immediately clear. That said, they could have quite
easily machine FOUR grooves in the bolt, and allowed for larger wires
AND thicker insulation. They could even have used 'extra flexible'
silicone-sheathed wires and the cost could only have gone UP by a few
dollars.

And the FinderScope and/or balance issue. Yes, at the start of my
evening of problems, I was using my trusty 'Rifle Scope' - mounted on
the front end of the OTA using Velcro bands and some small patches of
anti-slip rubber matting. It was certainly a huge improvement on the
Mead unit, even though the scope is only a 6 x 40 device. The image was
MUCH brighter (due to the larger aperture, and the lack of grease on the
eyepiece) and it was MUCH more accurately aligned - due the accurate
windage and elevation setting screws that a rifle-scope provides. But I
removed it when I dismantled the scope mid-evening, just in case
'balance' was an issue. I had hoped to counteract the extra 'nose'
weight when I attached my digital camera - had I ever been able to track
successfully that evening! I will 'start again' if I get a replacement
RA Finderscope once the unit is back from Meade.

So, now all I need are clear skies . . . . . .

Cheers,
Niall

Subject: RE: ETX-105 End Stops and Problems - a continuing saga
Date: 1/14/04, 18:38
From: Niall Saunders (niall@njs101.com)
Sorry it has taken so long for me to respond to your kind emails - but I
have been trying to actually USE my ETX-105 whenever the dreadful
weather conditions we are experiencing here in Aberdeen permit.

However, tonight was the last straw. Thankfully I surrendered my shotgun
licence a few years ago, otherwise I PROMISE I would have blown the
useless piece of junk clean off its tripod.

I consider myself thoroughly computer literate, I have a degree in
Electronics and studied Astrophysics at M.I.T. - I can dismantle a C.D.
player, replace its laser and recalibrate it; I can take a mobile phone
to pieces, locate a faulty surface mount component and replace that, I
can program microcomputers, microcontrollers, FPGA ASIC chips, and can
even get Microsoft Windows to behave; I can align a fully stabilised
2.7m communications dish to a geo-stationary satellite in orbit, whilst
on a vessel at sea, rolling +/-20 degrees in all three axes; I can strip
and rebuild a V8 Landrover engine (and its gearbox and transmission);
and I can Gas, Arc, MIG and TIG weld; and I can operate a Lathe or a
Milling Machine.

But the ETX has me beat.

Tonight we had about 5 hours of PERFECT skies - in between two frontal
systems that otherwise wiped everything out with 100% cloud cover. Using
a fifty-year-old 4" Refractor on an Alt-Az tripod made from little more
than 6-foot long 2"x1"'s I was able to marvel at all three major rings
on Saturn; one of the nicest views I have ever had of M-42 in Orion;
M-57 was so obviously a 'ring'; the Andromeda Galaxy (M-33) was
breathtaking; Ceres-1 could be seen in Gemini, as could the Eskimo
Cluster; and I could 'split the doubles' in Epsilon Lyrae.

But the ETX-105 took TWO HOURS to TOTALLY FAIL in all alignment
attempts.

Firstly, I use a DIGITAL INCLINOMETER (accurate to 0.1 degree, and in
FULL CALIBRATION) to set the top of the #887 De-Luxe (ha-bloody-ha!!)
Tripod to be LEVEL in two orthogonal axes (by adjusting leg length). At
the same time I will have set the 'leading leg' to as close to Celestial
North as I can manage.

I raise the tripod 'wedge' to a HIGH elevation, as this tilts the whole
scope forward, allowing me to place the digital inclinometer across the
rear faces of the forks, thus guaranteeing that the forks are parallel
to the ground, and also therefore orthogonal to the earth's polar axis.

I then lower the 'wedge' back down to the compliment of my Latitude 32.8
degrees(complimenting the 57.2 degrees for my home address - which I
know to within 3m accuracy from Differentially-Corrected GPS readings),
and which I can set to within +/- 0.2 degrees accuracy with the aid of
my Digital Inclinometer (I can't get the angle any more accurate,
because the Deluxe Tripod is too cheap to offer anything more than the
coarsest of adjustments, but I try my best).

I then tilt the OTA such that the body is at the same angle as my
Latitude (and I double check by taking a reading of the complimentary
angle across the face of the objective end of the OTA).

I can't use the Meade (or similar) instructions to otherwise set the
POLAR HOME position - because my ETX-105 absolutely, positively DOES NOT
HAVE END-STOPS. (and I have checked by rotating the base THREE FULL
TURNS anti-clockwise, followed by SIX FULL TURNS clockwise, and then
back to the mid-point with three more turns anti-clockwise. There is no
end-stop, nor any hint of such.

As prompted by the proprietor of the dealership that supplied the scope,
I had already removed the three rubber 'feet' and had looked inside the
base assembly. I was horrified by the state of the twisted Az/Dec feed
wires. The black outer sheath had 'knotted' itself up, and then
subsequently had 'split' a few millimetres from the RA/Az axis bolt. The
blue wire had even had its insulation stripped - although fortunately
was not rubbing against anything. So, having seen this, I knew that I
must always be 'conscious' of how many AZIMUTH turns the scope was
making, always ensuring that either the Autostar, or me, 'unwound' the
scope back to the position I had left the wires in prior to refitting
the base assembly lid.

So, the process described is the one I have to use for initialisation.

With the Autostar and power still disconnected, I check my polar
alignment using the 26mm lens (57x magnification, approx 1 degree FOV).
If I am lucky - and I am usually NOT !! - Polaris 'might' be in the main
FOV. I cannot use the 8 x 25 R.A. viewfinder, it is utterly useless. A
plastic scope from a Christmas Cracker would work better! The
finderscope ONLY focuses in the centre 1/8th of the 7.5 degree FOV. This
appears to be due to a film of grease covering the entire eyepiece, as a
result of the viscous lubricant used in the focussing ring. I dare not
clean it as I am concerned that anything stronger than heavy breathing
might dissolve the finderscope completely.

So, I probably need to adjust the scope to centre on Polaris. Forget
about using Kochab's Clock or anything that sophisticated. Just getting
Polaris into the main FOV must be considered a successful evening's
entertainment. If I am REALLY LUCKY, I might just need to compensate in
declination (Azimuth). On the basis that I feel the Autostar will want
to 'start' from the 'Home' position I do not touch the OTA, and instead
I adjust the elevation rod on the #887 Tripod 'wedge'. I am getting
'good' at putting in 'fine adjustments'.

But, if I need to adjust 'sideways' the the polar-oriented RA/Azimuth
axis is of NO USE to me (apart from the fact that I don't want to adjust
the 'HOME' position). So, I have NO ALTERNATIVE but to physically move
the WHOLE TRIPOD (because Meade were to 'tight' to offer an azimuth
adjustment on their 'deluxe' scope). Now, of course, I have to consider
the 'level' of the tripod all over again. I have decided now that I will
ONLY adjust the two 'lateral' (East/West) legs when trying to 'centre'
Polaris (as far as 'azimuth' in the viewfinder is concerned). If I can
get the tripod adjusted to have Polaris 'centred' (in Azimuth at least)
AND I have the tripod top plate 'level' (in the 'East/West' axis
anyway), THEN I see no reason why I cannot use EITHER the 'leading leg'
of the tripod OR the 'latitude adjustment rod' to get the base of the
ETX set to the correct angle (this being the compliment of my Latitude).
So, I choose to use the latitude adjustment rod, because this is easier
to do when looking through the eyepiece.

So, anything up to an hour after first going outside, I 'should' have
Polaris centred in my 1 degree FOV. At least the delay allows the scope
to settle into thermal equilibrium. As I said, Kochab's Clock - forget
it. Polaris ANYWHERE in the FOV is often the best I can manage.

Now I power up. I am running from a 12V 17Ah, fully charged
'Porta-Power' pack. If this can start my V8 Landrover it can surely run
my itty-bitty ETX scope. (I have tried running 'direct' from the 12V
battery AND from a LAB-QUALITY 12 mains power supply unit - what happens
next is basically the same)

I enter the date, and the time - accurate to the nearest second from my
GPS receiver. And I will have entered my Lat/Long from the GPS as well -
although I am surprised that the Autostar doesn't ask for the position
in any greater detail. I select Daylight Saving Time as "OFF" (although
I experimented with the "ON" setting just to see what the difference was
- a 15 degree 'sky error' just as I would have expected).

And now the REAL FUN BEGINS.

I ask for an EASY ALIGN, and off the scope slews to PROCYON (obviously
the Autostar's favourite choice for my location, my viewing time, and
this time of year). However, when the glorious fanfare is eventually
sounded by the Autostar, I can usually see that the OTA is 'miles off' -
looking up the OTA I can see that Procyon is off by the 'width of the
OTA' (or about 5 degrees of arc). I have tried TWO things at this point.
One is to use the slew buttons to get the OTA 'on-line', the other is
just to physically move the OTA, by hand' until I get Procyon centred.
Nether two methods seems to make much difference thereafter.

Then I press ENTER as usual, and off we go to Aldebaran. Again I can
expect up to 5 or so arc-degrees of error, but now I feel that I HAVE to
use the slew-buttons to get Aldebaran centred. Finally I press ENTER
again, and hold my breath.

I don't know why, because the usual response is ALIGNMENT FAILED, and I
have to go all the way back to Polar Home once again, and start all
over. If I am TRULY lucky, I 'might' get an ALIGNMENT SUCCESSFUL, not
that it does me much good, because any subsequent GO TO's will usually
only put the target in the (un-useable) FOV of the Finderscope, never in
the FOV of the OTA.. If I manually slew to centre something like Saturn,
then sidereal tracking is all but hopeless. A few minutes in a low
magnification eyepiece is the best that I have ever achieved.

However, tonight the gremlins truly conspired against me. As the night
wore on, I started to get 'MOTOR UNIT FAULTS' as soon as the scope
started to slew toward Procyon - always in roughly the same position of
RA/Dec. So, unwillingly , I resorted to the RESET; CALIBRATE; TRAIN
DRIVES routine that Dr. Clay recommends. I did SEVERAL of these - to no
avail. I then did DOUBLE RESETS, followed by DOUBLE CALIBRATES, followed
by DOUBLE TRAIN DIVES (and I knew to make sure that I was training BOTH
axes, although the Autostar 'user interface' at that particular -
critical - stage is ABYSMAL).

I checked 'Battery Voltage' - it was at 100% (actually 12.867V by my
calibrated Digital Multimeter - surely a 'digital' readout could not
have been THAT difficult to implement on the Autostar???). The outside
ambient temperature was just around freezing, with frost on the grass,
but the Autostar had been in my hand for the better part of two hours by
this time.

So, with no access to my shotgun, I decided to get the system 'opened
up'. I virtually no longer cared about my warranty - if this was the
best that Meade could supply by way of Quality Control, it seemed
unlikely that they could do any better 'second time around'.

Although I had suffered numerous 'M.U.F.s' when running the DEC/Alt axis
at full slew speed, when I opened the base the DEC/Alt wires, previously
seen as 'damaged', seemed no worse - although I decided to strip the
damaged outer black sheath to relieve the strain, just in case.

This time though, I also decided to look more closely at the RA/Az motor
and gear train. The first thing I noticed (apart from a generous spray
of 'Mexican Green Goo' everywhere) was that ALL THREE screws holding the
drive assembly to the chassis were VERY loose - one screw was only just
staying in place. I CAREFULLY tightened these, as it was obvious that
ANY excess force would strip the thread out of the cast alloy base. I
also could 'just' see that there was green grease around and about the
plastic wheel that serves as a position sensor for the gear train. So I
removed the two screws holding the drive PCB in place, and watched BOTH
of the IDC connectors FALL OFF their header pins (the four-way connector
feeding the Autostar AND the two-way connector feeding the motor).
Fortunately I had already sketched their locations (blue wire to the
'inside' of the PCB on the 4-way, and black wire to the 'inside' of the
PCB on the 2-way). I carefully 'rearranged' the header pins so that,
when reassembled, the artificial mis-alignment would serve to make a
firmer connection.

Using methylated spirits (I couldn't be bothered to find my Isopropyl
Alcohol, and I was already drinking the Single Malt, and wasn't going to
waste THAT on this mickey-mouse gearbox) I cleaned all the mexi-snot off
the sensors, and also off the slotted disc as well. I also removed a
good half-teaspoonful from the remainder of the gear-train as it seemed
that the Mexican assembly line instructions are to "use plenty, and then
add a good dollop extra, just for good measure".

Then I removed the two little screws from the inside of the fork that
contains the DEC/Alt drive mechanism. I also removed the 'knurled clamp'
and the 'non-enumerated' disc to reveal a further, slightly longer,
screw that, when removed, allowed the outer cover of the fork to be
removed. It was at least nice to see that the ETX-105 does use a LOT
MORE cast alloy than its predecessors (the ETX-90 and ETX-125). There
seemed to be little evidence of 'grease spatter' on the DEC/Alt
mechanism - such that there was did NOT seem to be getting anywhere near
the slotted disc, so a brief clean (and another sniff of the Meths) and
all was deemed 'OK'. What I did do was to thoroughly 'de-oil' the little
brass ring that sits between the large aluminium disc and the DEC/Alt
bearing. I felt that the 'less' lubricant on this item would lead to
'less' force required to 'clamp' the DEC/Alt axis (especially useful if
trying to load a digital camera onto the OTA). The DEC/Alt 'clutch' IS
in fact this little brass ring - which is clamped down, by the knurled
knob, between the large aluminium (graduated but non-enumerated) disc
and the inner race of the ball-bearing.

So, feeling that I had addressed SOME of the obvious faults on the unit,
I went back outside (two hours of 10/10 viewing had elapsed !!) and
tried to re-align on Polaris (after taking the time to
RESET/CALIBRATE/TRAIN - AND to ensure that ALL of the other parameters
had been correctly set: Scope Type, Scope Mount, Site Location etc. -
and to record that the Autostar software is 2.6Ec). The Autostar started
off towards Procyon for the Easy Align and, at the same point as before,
ANOTHER damned M.U.F. - this time I just stopped the OTA where it was
and worked BOTH axes (individually and together) at FULL slew speed back
and forth (360 degrees in Azimuth, 90 in Altitude). I did this for TEN
MINUTES, with no further MUF's.

Back to the beginning again - although this time I could hardly see
Polaris because the clouds were now rolling in. And then off to Procyon
- but, when the OTA got there, Procyon was GONE. In fact the WHOLE sky
was now obscured - except for a small patch just visible up the side of
my house - where some unidentified star had just climbed out of the
Eastern horizon. I tried to slew to the star, hoping to see if the
Autostar would at least manage some form of sidereal tracking - only
this time I encountered (for the FIRST TIME) the 'creep after slew' and
'rubber-banding' issues I have heard others describe.

I gave up in disgust. Despite everything being reasonably damp I
couldn't even be bothered to take my normal 'dew' precautions, and just
heaved the whole (expletive deleted!!) sorry mess into my hallway -
pending further disposal measures.

My question now is :

"Am I doing something wrong, or am I just stupid?"

And, by the way Mike, I have read EVERY SINGLE page of your site - and
the LDX site - and most of Dr. Clay's pages, AND the whole of the Meade
site (including downloading the 300Mb of their 2003 catalogue in PDF
format) and so feel that I am covering MOST, if not ALL of the 'common
mistakes' that new ETX users make.

If you decide to 'publish' this lengthy 'grumble' (and you have my
permission to do so) then all I ask is for someone, anyone, to let me
know if I am making some un-noticed fundamental mistake when trying to
use my ETX. Failing that, then I dread hearing the standard response of
'back to Meade it will have to go'.

Thanks in advance.

Niall Saunders

And:

Thanks for getting back to me so quickly. You are absolutely right about
going 'back to basics', and that is exactly what I intend to try on the
next clear night. Prior to that I will do a full Reset (again), followed
by a Calibrate and Dual-Axis Train Motors routine (ensuring that this
time I am in Alt/Az mode). I will feed back my results.

As far as Meade and my Dealer are concerned, I have spoken briefly to
Meade to ask about their returns procedure, and at length to the
'original' dealer - who has been more than helpful (Mr. Papagno, of
F1Cameras.co.uk). It would seem certain that the scope will be making a
trip back to Meade (fortunately without the 'shotgun' evidence!).

In the meantime, could anyone perhaps contribute to what scenario
actually causes the "Alignment Unsuccessful" error message? (Perhaps the
same question could be asked of the "Motor Unit Fault" message, although
I am going back to re-read some of the Technical Information already
gleaned from your site - I seem to remember having come across THAT
answer before!)

Once again, both myself and the ETX community are indebted to the
service your site provides.

Niall Saunders
Aberdeen, Scotland

And:

I am spending a few minutes on the Cloudy Nights website, then I'll be
back to yours for another 'marathon session'. Who says learning stops
when you graduate?

Cheers,
Niall

Subject: First Time Novice Observations with the ETX105 and a reply to Nick Preece
Date: 1/9/04, 18:40
From: Larry Somers (lsomers@cox.net)
Nick,

Like you, I am new to telescopes. After doing my research and finding
Mike Weasner's great site, My wife and I went ahead and purchased an ETX
105EC with UTHC, Autostar Controller, & 884 Tripod, for Christmas.

I found that setting it up initially and training the motors was
actually very easy  but essential prior to first use.  Youll want to
do this during the daylight!  The one thing I found confusing was how to
align the scope.  The instruction manual, the tripod manual, and the
Autostar manual all give instructions on alignment. I was confused 
which method to use?  So my first attempt  polar alignment  resulted
in what seemed to me to be a very unsteady telescope.  As I was
unconvinced that I had done this correctly I drove on down to the local
telescope store (Oceanside Photo and Telescope) and asked if they could
quickly show me.  Basically, it took them all of about 2 minutes to show
me the correct way (Alt/Az) for easy alignment with Autostar.  So, I
suggest, have someone familiar with the ETX show you and/or follow the
Autostar manual. The Easy Align is very easy and the way to go to get
started.

So that night, New Years eve, around 11:30 PM, I brought the scope
outside and did my best to align the ETX following the Autostar Easy
Align instructions.  Basically all you do is 1) level the scope, 2)
point it North (Home position), 3) engage the horizontal and vertical
locks, 4) Tell Autostar to align the scope. My backyard faces south, so
I couldnt see the north star, and I didnt have a compass, so I only
guessed on pointing the scope north. I then told Autostar to do its
stuff (Easy Align) and, to my amazement and luck it automatically slewed
to Polaris in the southern sky.  I didnt know it was Polaris but I just
followed the directions and centered the brightest star I saw in that
region of sky in my telescopes eyepiece, and told Autostar it was
centered.  Autostar then automatically slewed my scope to Aldebaran in
the South West, I again centered the brightest star in that region of
sky in the scopes eyepiece, told Autostar it was centered and tada  the
scope was aligned!  Not believing it could be that easy I then told
Autostar to GoTo the moon. Again, to my amazement, the scope slewed
automatically to the moon  right on!  After viewing the moon for some
time, at midnight I tried the ultimate test and told Autostar to find
Jupiter and then Saturn.  Again, to my amazement, the scope slewed
immediately to each planet.  I could make out some banding on Jupiter
and the rings of Saturn using my 26 mm eyepiece.

After focusing on Saturn, I replaced the 26mm eyepiece with an
inexpensive 6 mm GSO eyepiece.  Immediately the planet disappeared from
view and I spent about a hour finding and refocusing the telescope on
Saturn.  Autostar is of no help at this point.  It was difficult to
focus perfectly because even touching the focus knob moved the planet
out of the field of focus. Also, since the 6 mm eyepiece is much shorter
then the 26mm eyepiece, the longer eyepiece of the spotting scope, which
is mounted just to the left of the eyepiece, makes it difficult for you
to view with your right eye.

After refining the Autostar tracking a few times the scope tracked the
plant perfectly until we were ready to stop for the night. I was able to
just make out the division in the rings of Saturn but thats all. I am
hopeful that a better quality eyepiece will give me better results in
the future.

I think the biggest reasons for my success were:

   1. Training the telescope during the daylight  an easy task but one
   I suspect is most critical to getting Autostar to work correctly.

   2. Learning the correct way to align the scope (Easy Align).  This is
   very easy but because there are several different ways to align a
   telescope it is easy for 1st timers to get confused.

   3. Learn how to tell Autostar to refine the alignment once you focus
   on an object.  This really improves tracking of the object.

The Good & the Bad of the ETX 105  my opinion! I would appreciate the
views of Mike and others regarding these items.

The Good: 

    * Optics: The optics of the scope seems to be superb. The moon and
    its creators are sharp as a tack with no color fringes that Ive
    notice.

    * Autostar seems to work great if the scope has been trained and
    aligned correctly.  Just what the novice (me) needed to start
    finding objects.

    * 884 Field Tripod:  Solid and well matched to the 105EX.  This is
    important as the slightest movement of the scope, when observing
    with a high power objective, will cause the object to move out of
    the field of view.

    * Portability. Because we have a small back yard with a fence around
    it I wanted a scope I could hall up the mountain near our house.
    This should be no problem with the EX 105.

The Bad:

    * Vertical Lock: I find the Vertical Lock on the ETX scopes to be
    its most serious week point. Its essential that the scope be
    vertically and horizontally locked to engage the motor drive.  With
    such a good tripod, the last thing I expected was that the fork
    mount would not hold the scope steady! The Vertical Lock does not
    secure the scope from up and down movement very well. The result is
    that the user tends to over-tighten the vertical lock trying to make
    the tube steady. I checked this on a EXT125 in the showroom of a
    local dealer and it was no better then mine.

    This also makes the addition of a heavy camera very difficult.  I
    suggest you research this issue prior to making your final decision.
     There are several comments about this problem on this very web
    site.  Maybe Mike has something more to say on this issue???

    * Focus Knob: This knob is at the back of the scope.  When the scope
    is pointing directly overhead the knob is next to the base making it
    difficult to turn to focus the scope.  Also, with a high power
    eyepiece adjusting the focus, which is essential when a different
    eyepiece is inserted, often causes the object to move out of the
    field of focus. A good solution may be the Flexi-Focus from the
    folks at http://www.scopetronix.com.

    * Auto Star Arrow Keys: It seems that the arrow keys on the Autostar
    controller dont always seem to move the telescope.  Sometime they
    just seem to be dead!  I found the solution is to press one of the
    number keys which, in turn, select the telescope motor speed. Then
    the arrow keys work again.  Mike  any ideas on this??

    * Spotting Scope Eyepiece: Because the spotting scope eyepiece is
    mounted just to the left of the telescopes eyepiece it gets in the
    way when using short, high power eyepieces and viewing with your
    right eye.

Conclusion:

Im glad I purchased this scope and I believe it is of good quality for
the cost. With Autostar, it is easy to learn to use for the novice. 
Possible, with experience, some of the item I had trouble with will
become easier.  Still, considering the number of other people with
similar complaints, It would be even better if Meade would redesign the
vertical lock and focus knob!

Good Luck!

Larry & Kathi Somers

Rancho Santa Margarita, CA.

Subject: ETX 105??
Date: 1/6/04, 11:46
From: Nick Preece (nick.preece1@btinternet.com)
Firstly, let me introduce myself. My name is Nick, I'm 29 years old and
from Hereford in England, UK. I have little or no experience as an
amateur astronomer and have never owned a telescope!! Hence the need for
some advice from an expert.

You've got a wicked website by the way!! Nice to see one that gives you
the answers and information that you need rather than an endless stream
of fancy pictures, animations and the usual rubbish associated with so
called state of the art sites. Yours was very informative and I spent
over three hours browsing it the first visit!! The picture galleries are
amazing. I never realised amateur astronomers would have the resources
to take such detailed pictures so far out into space!!

Anyway, down to the nitty gritty!!

I've always been very interested in the skies and planets etc. but never
thought it would be financially possible to afford a decent telescope to
do the job. My wife and I have just moved from our small city of
Hereford to a little hamlet in the country. Our house is situated on a
hill and we can see for miles all around, so as you can imagine, without
street lights anywhere near us and the situation of the house the views
of the sky on a clear night are awesome!!

Jo (my wife), new I was toying with the idea of  buying a telescope so
she decided to buy me one for Christmas. However, the telescope she
bought was a very budget affair which was very hard to stabilise and not
much use for more than a quick glance at the moon. (nice of her to try
though, eh!!). So, we have returned the said telescope and I have been
searching the internet for advice on buying a decent one. Your site was
the only one which gave me any help at all.

The telescope I think I would like is a Meade ETX 105? The only thing
that bothers me is that I feel it may be too advanced for me? What do
you think?

Reading some of your articles from other astronomers having problems
with training the motors and setting magnetic poles (whatever that
is!!), are these things really as hard to get your head round as they
sound? As you can tell I have not a clue about astronomy so I really
would be starting from scratch.

What I really don't want to do is buy a telescope that I will be
disappointed with in a few months time.

I have been comparing prices of these ETX 105's and you lot across the
water get a lot more for your money than we do!! An etx 105 over here
costs around 700, that's almost $1300. Whereas I have found an ETX 125
in the USA for $899, that's just 500 in our yard. It's almost worth me
travelling over and picking one up as well as having a holiday rather
than paying our over inflated prices!!

Unless you know of a cheaper way or dealer I can get one from?

Anyway, I have bored you silly now so I will say goodbye.

Congratulations once again on the website.

Hope to speak to you soon

Best wishes

Nick Preece.

And:

Many thanks for taking the time to give me your thoughts. I will keep
you posted on how I get on!!

Bye for now

Best wishes

Nick.

Subject: ETX-105 RA Hard Stops
Date: 1/5/04, 12:52
From: Don Sutherland (don_sutherland@yahoo.ca)
Niall Saunders was wondering if the ETX-105 had hard stops. I received
my ETX-105 UHTC in June 2003. It does indeed have hard stops, just under
2 full turns apart.

Like Niall, I was appalled at the arrangement of the wires to the Dec
drive. The wires to my Dec drive were severed by the RA drive gears
shortly after I received my scope.

I plan to replace the original wires with a "clock-spring" made from
ribbon cable. This is what the auto makers use to connect the switches
and air bag mounted the steering wheel of a car. If anyone has built a
clock-spring for the Dec drive cable, please e-mail details to Mike.

In the interim, I put a cardboard disc between the coil of wire and the
RA drive gears. The disc is about 3" in diameter with a small hole in
the center and a slit running from the circumference to the center hole.
The wires to the Dec drive are slipped through the slit to the hole in
the center. This seems to keeps the wires out of the hungry jaws of the
RA drive.

Regards,
 
Don Sutherland

Subject: ETX-105 (UHTC) RA question
Date: 1/2/04, 15:31
From: Niall Saunders (niall@njs101.com)
I recently purchased an ETX-105 (with UHTC coatings, so assumed to be
'very new'). Having spent hundreds of hours looking through your site
before 'taking the plunge' I felt that I would be fairly 'familiar' with
the scope when it eventually arrived.

Before even powering it up, I set out to establish it in an Alt-Az
'Home' position. However, there was NO INDICATION WHATSOEVER of ANY kind
of mechanical end-stop on the RA/Azimuth axis. (There are no problems on
the Dec/Alt axis).

I have tried THREE full (manual) turns clockwise and anti-clockwise
(very gently, and very carefully) and I do not come up against any
end-stop at all. So, sitting in front of a BRAND-NEW (!!) $1000 scope,
and armed with a dentist's pick and a pozi-drive screwdriver, I
carefully opened the base of the unit, making sure that no wires were
stretched, and nothing was compromised. Imagine my dismay to discover
that the four wires, along with the black plastic shrink-wrap sheath,
that lead up through the groove in the RA/Az fixing bolt were
HORRENDOUSLY twisted. In fact they had been so badly twisted that the
shrink-wrap sheath had split, and the insulation on the blue wire had
parted.

I carefully 'unwound' the twist - by turning the base unit in the
appropriate direction until the strain had been relieved. Matters had
been made worse by the fact that the four-wire 'cable' was wrapped round
one of the base-mounting pillars (presumably originally for cable
strain-relief). Further, just the fact that the shrink-wrap sheath had
been fitted meant that the individual wires could not twist along the
full length of the available cable - instead the twists had been
concentrated at the exit point of the groove in the bolt.

I have spoken to the dealer, mentioning the apparent lack of an
end-stop, and he (fortunately) suggested that I 'take a look inside the
base' just to see how bad things were (so, I don't feel that my warranty
should have been affected - as the suggestion to do just that had come
from my Dealer!). He certainly suggests that it goes back to Meade (UK),
and I will be doing just that - but not until the long dark nights have
passed, or until my next door neighbour takes delivery of his 8" LX90.

But, the question I need answered is this: "Should there be a pair of
mechanical end-stops on the latest chassis of the ETX-105 models, or has
the need for end-stops been alleviated by the 'Cord Unwrap' facility
present in my Autostar?"

In any case, until such time as it fails completely, everything has been
working fine. I just make sure that I do NOT manually move the RA/Az
axis more than 180degrees, and I ALWAYS use the 'Park Scope' command at
the end of a viewing session. This alone, albeit along with the fact
that the v2.6 AutoStar software seems to 'know' how far it has rotated
in RA/Az, has seemingly prevented any FURTHER damage to the Dec/Alt
power and signal feeds.

The only other question is "Why don't Meade just provide a pair of 'AUX'
connectors - one on the DEC/Alt fork containing the motors, and one on
the base unit. That way, an external 'curly-cable' could have been used
on the whole ETX range, and the 'cable-through-the-bolt' problem could
have been avoided completely. Easier to implement, and cheaper than a
4-pole slip-ring on the RA/Az axis. After all, those users with
Electronic Focusers already have a cable-wrap problem to contend with,
and their curly-cable solution seems to work fine. (Come on Meade, get
with the program, and start listening to customer feedback!!).

Thanks in advance.

Regards,
Niall Saunders
Aberdeen, Scotland

And:

The control panel is still on the base - to all intents and purposes no
difference between 'standard' ETX models, familiar to all of us.

Yes, I have enabled 'Cord Wrap', and this seems to now be the ONLY level
of protection that I have. I appreciate that you, personally do not have
the ETX-105, but I am hoping that other (Clay Sherrod included) may have
a definitive answer on this one (if indeed you do not have a friendly
Meade engineer to whom you can pose the question).

It is also interesting to note that there does not appear to be any form
of 'serial number' identification on the telescope assembly itself
(other than an 'inspected by' number on the OTA). How on earth do Meade
establish whether a particular telescope is actually worthy of warranty
repair?

I will pass on my experience with Meade (UK), from here in Scotland, so
that others might benefit.

Thanks for taking the time to reply (as the leading contributor to a GPS
users Forum on the internet, I know how time consuming it can be,
dealing with upwards of a hundred emails a day!!).

Regards,
Niall

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