26 replies to this topic

[Mhanna]

Greetings!

 

Thank you for having me on this forum, this is my first post.

 

I was wondering if there is someone that may be able to assist with a new Goto Telescope I bought over the weekend. Any help or assistance will be greatly appreciated.

 

I bought a Meade ETX 125 Audiostar/GOTO scope on the weekend. I've had 2 clear nights thus far but haven't been able to align it properly. First of all, I live in Adelaide, Australia, which is in the southern hemisphere. When I first got the scope, it was constantly circling which was strange. I did a reset and re-set up the scope and that weird behavour went away. I entered the language, location (AUS->Adelaide), date, time, and telescope model all fine. I then leveled the scope mount, attached the scope to the mount, and pointed the scope compass north and at 0 degress (flat), which from what I can tell is considered the home setting.

 

This is where the alignment process starts getting strange. If I do a 2 star alignment, it moves to the first star and awaits for me to center it and press enter. The problem is, it's slewed to an area that is absolutely no where near - I mean it will point in the complete opposite direction to where it thinks the star is. Almost as though the start position was completely wrong. If i slew it to the star and center it, which is in a completely different portion of the sky, the scope gets confused and alignment actually fails. Turn off, start again. Obviously there is a threshold of how far the centering can take place before something is considered wrong and I'm going over that. If I run through any if the 2/1/Easy alignment processes, with or without a little bit of centering movement (for testing), the scope will accept and alignment successful is displayed on the control unit. If i then use the scope with these so called inaccurate alignments, it's completely off, like slewing to the moon, mars, saturn or jupiter. Ask the scope to go there and it will point in a completely different direction. Also, ask the scope to go to a star that you know and can see with the naked eye, but it won't becuase it thinks it's below the horizon.

 

To me, it seems as though my start position prior to alignment is wrong. The scope knows where it is, with the correct time, location, and even slightly altered lat/long for my exact location. I also tested using the high precision feature, but that didn't do too much.

 

I am plugged in using AC power. The scope itself moves fine, and the optics are better than I expected (Ie; I am happy with the optics - I can see saturns rings crystal clear with the included 9.6mm).

 

If there is someone who would be able to assist, I would be eternally greatfull, perhaps someone who both knows the ETX's or meade's and who lives locally I should also point out, this is my first computerised scope - I have both patience and logic, so believe there is nothing wrong with the scope, but perhaps something wrong with me (ie; my starting position)

 

Thanking you in advance.

 

Matt

 

PS. I've also set up the red dot finder and have red the instruction manual several times / watched many youtube videos on it. I have also done a motor calibration.

Edited by Mhanna, 21 October 2018 - 04:57 PM.

[Mhanna]

Oh, I should mention, this is the newer version telescope - it has no hard stop. There is no switch on the bottom to flip between southern and northern hemisphere either.

[OzAndrewJ]

Gday Matt

 

pointed the scope compass north and at 0 degress (flat), which from what I can tell is considered the home setting.

Not sure what you mean by "the scope compass"

What Firmware ??

The start position for a manual 2 star align is with the OTA level and pointing True North.

After that, as long as you have selected ETX-125 as the model, it should point reasonably accurately to the first star.

If it doesnt do that from the correct start position, then extra tests will be required to see if the encoders are working properly, or there is a time error.

 

Also, ask the scope to go to a star that you know and can see with the naked eye, but it won't becuase it thinks it's below the horizon.

If it thinks it is "below horizon" vs "exceed limits", it indicates a time error

If you go to the web, you can find online sidereal clocks, which will give the LST for Adelaide.

After setting the date/time in the hbx, press and hold the mode key for say 6 seconds and release.

This brings up an alternate menu. Scrol down till you get to the local time and LST display.

Are both times correct????

 

Obviously there is a threshold of how far the centering can take place before something is considered wrong

Not really. The scope soesnt really care how far you move to centre the first star.

It only gets upset if the second star is badly off relative to the first one.

 

Andrew Johansen Melbourne Australia

Edited by OzAndrewJ, 22 October 2018 - 03:44 AM.

[Mhanna]

Gday Matt

 

Not sure what you mean by "the scope compass"

What Firmware ??

The start position for a manual 2 star align is with the OTA level and pointing True North.

After that, as long as you have selected ETX-125 as the model, it should point reasonably accurately to the first star.

If it doesnt do that from the correct start position, then extra tests will be required to see if the encoders are working properly, or there is a time error.

 

If it thinks it is "below horizon" vs "exceed limits", it indicates a time error

If you go to the web, you can find online sidereal clocks, which will give the LST for Adelaide.

After setting the date/time in the hbx, press and hold the mode key for say 6 seconds and release.

This brings up an alternate menu. Scrol down till you get to the local time and LST display.

Are both times correct????

 

Not really. The scope soesnt really care how far you move to centre the first star.

It only gets upset if the second star is badly off relative to the first one.

 

Andrew Johansen Melbourne Australia

Hi Andrew,

 

For attempting the 2 star alignment I've been pointing the ota to compass north - I thought true north were for people in the northern hemisphere being able to directly reference polaris.

 

The firmware is A4S1.

 

What I meant by the scope compass was the cheap little bubble compass/level which comes with the scope that is supposed to sit in the eyepiece holder.... I've been using a phone app instead (in tandom).

 

I did read a different thread with your suggestion on how to use sidereal time. There was a URL there but the link was broken. I havent been able to find a useable link on the web about it yet but will keep looking becuase that seems like a great time setting verification step.

 

Interestingly, an hour ago I changed the telescope type to ETX90 and re-performed the tests, and things were different. I'm not quite sure why they were different now, because earlier today I did exactly that and things were way off, in other directions off. The cloud has covered over so Im not able to go outside with the scope and properly test.

 

For true north, would it be a matter of finding polaris on my phone app laying inline and flat on my OTA, then pointing straight at that?

 

Thanks kindly

 

Matt

[Mhanna]

https://www.heavens-...&alt=58&tz=ACST

 

I will check this tomorrow against the scope

[aeajr]

Mhanna,

 

Welcome to Cloudy Nights.  

 

I have owned the ETX 60.    I currently own the ETX 80 Observer, the same generation as yours.

 

I also own the ETX 125 EC, an older model that was not originally GoTo, but the GoTo handset was added later.

 

 

I have read through your notes and it looks like you are doing things correctly.   Here are two thoughts:

 

1) If you entered your Lat/Lon into the handset, make sure you have the correct sign on those numbers  They can be positive or negative.    For example, Sydney is -33.868820 and 151.209290 .   Note the negative.

 

Another thing to check is to be sure your set for AltAz and not equatorial coordinates.   I thought this was a menu choice but looking through the manual for the Observer series I don't see it in the menu tree.  I have never tried EQ alignment with my scopes and don't know what behavior that would drive, but it is worth a check.   

 

This is from the old ETX 125 EC manual and may not apply to the newer models. 

 

Easy (Two-Star) Align

The fastest and easiest way to locate celestial objects is to use the alt/az Easy Align.
Autostar is in the alt/az mode when you first power it on, so you do not need to select
this mode, unless you have changed this setting in the Telescope/Mount menu. If you
wish to align your telescope in the equatorial (polar) mode, see EQUATORIAL
ALIGNMENT, 

 

In my two star alignment it gives me a choice of whether I am using magnetic north or true north, but even if I select that incorrectly, it will put me off by about 12 degrees, not on the opposite side of the sky.   But I am in New York, USA. 

 

 

If none of these help, I have to believe that this has something do do with your being in the southern hemisphere.   If the scope is coming up in nearly the opposite part of the sky this is my suspicion.    

 

My scopes don't always pick that first star perfectly but it is usually within 5 degrees and centering gets it properly aligned.

 

I would suggest you call Meade and share your issue.   I have found them to be very helpful.   It is possible your scope is defective.  It happens. 

 

 

Below is the step by step procedure I follow for set-up that I have documented to try and help other people.   As you noted, my ETX 125 EC and an LX200 I have used do  require me to go to the hard stop to set that boundary. The ETX 80 Observer does not.   I was not aware they had done away with the hard stop on the ETX 125 Observer.  But even if it were still there, the scope would still align properly but it might run into that stop during slewing.

 

 

If the above does not help I think ultimately you need to call Meade.

 

=================

I have owned the ETX 60, 80AT, 80 observer, 125 EC which has been converted to GoTo.   I have used the ETX 90 observer.    They all work the same as the brains are in the hand set.    So I will walk the process I follow and you let me know where you are having a problem.

 

• Power off
• Be sure you have fresh batteries or AC - low batteries will cause alignment and motor errors
• Set up tripod and scope - alt and az clutches are released.
• ​Tilt table is down, not raised
• Adjust the tripod legs if necessary to get level in all directions.
• Confirm level with the eyepiece level.   Just get it very close
• Set the scope (OTA)  approximately level and pointing either magnetic north or in the direction of Polaris but the OTA is level, not pointing at Polaris.

All confirmed?

• Lock the AZ clutch ( slide the lever right)
• Lock the Alt clutch ( firm not crazy tight)
• Power on
• Do not release the clutches at ANY time once you have powered up.
• replace the eyepiece level with an eyepiece - I usually use the 26 mm.

Next steps are all in the hand set.  I don't do this every time but you have to do these at least once, then the information is saved.  Let's just make sure

• Correct telescope is selected
• Correct time zone
• Make sure date and time are correct, to the minute.  Every minute error is a .25 degree/half the moon, targeting error
• Make sure you have the correct location – I think it accepts Zip codes in the USA. 
• DST, daylight savings time is on or off depending on time of year.  It should be off now.

Once all of this is confirmed, select EASY alignment - this is the two star alignment and the telescope chooses the stars

• I think it asks if you use magnetic ( using compass)  or true north, in the direction of Polaris
• Scope should select the first star and slew to it smoothly without slippage or jerking.
• Likely it will not hit it perfectly so you will have to adjust it with the hand set after it beeps.
• Once it beeps, use the arrows on the hand control to get the obvious bright star in the center of the eyepiece, hit enter. While it should be close, if your initial set-up is off the first star will be off.  Not an issue, just adjust it to center the star in the eyepiece.

If it seems that the scope is not moving when you hit the arrows it is on a very slow slew speed.  Hit number 5,6,7 or 8 to increase the slew speed and try again.

• Do not release the clutches or you will mess up everything.
• Scope will select the second star and slew to it smoothly and without slippage or jerking
• Using the hand control get the bright star centered in the eyepiece​, hit enter.
• You should get "alignment successful".

 

Areas where I have seen people have problems:

 

• Forgot to lock the clutches
• Released the clutches and moved the scope to align with the star - very bad
• Tripod is no where near level
• Mount table is raised - only for EQ alignment do you raise this.
• Forgot to hit enter after getting the star centered in the eyepiece
• Can't align to the star because the slew speed is too slow and they think nothing is moving when they hit the arrow keys.
• Centered in the finder scope, not in the eyepiece
• Batteries low
• Date and time off - every minute is a 1/4 degree error
• Location incorrect
• DST, daylight savings time, is incorrect - Introduces a 15 degree error if it is wrong.

 

So, where are you having problems?

[Mhanna]

Hi Ed,

 

Thanks for such a thorough post.

 

With this version, yep, no hard stop. They've clearly fixed that.

 

With the lat/log, +/- these cannot be entered but I assume the system just uses south/east or GPS (DMS) co ordinates. After I set the country and city it's pretty much spot on, I'm only a few kilometers from the city so I can probably get away with not changing those numbers at all.

 

I have a lot more playing with it tonight. The skys are clear again today so hopefully that holds off.

Edited by Mhanna, 22 October 2018 - 03:28 PM.

[aeajr]

Good luck with it.   And, again, don't hesitate to contact Meade if you continue to have problems tonight.

 

Here is the contact info.   At least post an e-mail to customer support if the phone support hours are not convenient.

https://www.meade.com/contact-us/

 

 

If you purchased this new from a local dealer, call them too.   Often they can help.  But don't delay as there may be a return for refund period in play.   

[OzAndrewJ]

Gday Matt

 

https://www.heavens-...&alt=58&tz=ACST

 

I will check this tomorrow against the scope

You can check it any time you like.

Basically boot up the scope indoors and set the date/time as per normal.

Then use the above app to confirm the Hbx is displaying the correct local year/date/time

and the reported LST is correct.

If not, there is a setting error somewhere.

Andrew Johansen Melbourne Australia

[OzAndrewJ]

Gday Matt

 

The firmware is A4S1.

(yuk )

 

For attempting the 2 star alignment I've been pointing the ota to compass north

OK, IIRC, there are 2 modes in these later Firmwares, "True North" and "Compass North"

and you get to choose what you want.

I always prefer "True North" as you cannot be sure the internal database of magnetic offsets it uses is correct for your location, ie it may over/under compensate vs reality.

 

I thought true north were for people in the northern hemisphere being able to directly reference polaris.

Nope.

When Meade say "Level North" it is the same for both hemispheres because it really means Az=Alt=0

but Level and North is easier for people to understand.

ie When set up for starting an align, you are really pointing the OTA to Azimuth and Altitude = 0, and the scope uses this as a start point for a dead reckoning slew to the first star.

By using Compass North, it is supposedly simpler, but can end up harder

 

Interestingly, an hour ago I changed the telescope type to ETX90 and re-performed the tests, and things were different.

As they will be.

Meade use the same handbox for all models. They also use a mount agnostic set of code.

To allow different mounts to function, they use a single mount specific variable called a "Ratio", which is in essence, the no of quadrature encoder transitions per arcsec of axle movement.

The ETX90 has a different ratio to the ETX-125s, hence you cant mix em up.

( The only proviso here is you are using A4S1, which is a truly horrible buggy firmware. In that version, they stuffed up the new ETX-90s, and gave them the ratio of the old ETX-90s instead, which wont work. For the new ETX-90 and A4S1, you need to select the mount as an ETX-80, but the ETX-125 isnt affected by this bug )

 

The cloud has covered over so Im not able to go outside with the scope and properly test.

You can still do dry tests indoors, ie do a dummy align, time tests and then gotos

You can use a planetarium to see where some of the brighter stars are, and hence see if it is getting in the ballpark.

 

For true north, would it be a matter of finding polaris on my phone app laying inline and flat on my OTA, then pointing straight at that?

 

Dunno, I would just look up a marine map/google map etc  of Adelaide that shows true North relative to your street alignments

and use that to begin with.

http://www.magnetic-...ide/116230.html

Once you get a good align in your yard, tell the scope to point to AZ = 0 and make a mark somewhere to show

what that angle is for future use. Anything within a few degrees is OK normally, as the target will appear in the red dot.

 

Andrew Johansen Melbourne Australia

Edited by OzAndrewJ, 22 October 2018 - 04:37 PM.

[Mhanna]

Hi Andrew and Ed,

 

Thank you both for your assistance and advice.

 

To answer all things from above;

 

I have been doing a lot of dry runs inside with goto over the last few days which is why I was so concerned. At times the scope was completely way off.

 

I installed a compass on my phone which show compass and true north at the same time.

 

Last night was quite clear here so I set it up and did further tests. I had the scope set to ETX 90, DST = YES, timezone to 9.5+ (I still need to play with that as I assume it should be 10.5+), did a 2 star alignment early before full darkness using 2 stars I knew. Things started working pretty well... it didn't quite get entirely exact but pretty close (may be the +9 vs. +10 timezone). All i did was swap between eyepieces to align centrally. There are a couple of variables that could now be fixed. Set to 10.5+ instead of 9.5+ with DST on (and test with DST off too), also do a train and calibrate.

 

I then set the scope to ETX 125. It's completely off. Not even close. Trying to do a 2 star alignment fails every time, and when i do a 1 star alignment, going to objects is anywhere up to 180 degress off (basically, it has no idea how to get where it needs to go). As previous comments, I will set this to ETX 90 and enjoy the viewing

 

Thank you all for helping

 

Cheers,

Matt

[OzAndrewJ]

Gday Matt

 

As to timezones, the data stored against the site should be the true Adelaide timezone without DST offset, ie 9.5.

You then use the specific DST setting prompt in the menus to tell it if you are in DST mode.

 

I had the scope set to ETX 90

...

I then set the scope to ETX 125. It's completely off.

Can you double check something for me then, ( as this isnt making sense )

( I mentioned A4S1 was orrible when tied to the new ETX-90s, but others reported the ETX-125 was OK )

Select as an ETX-90 and then go to the Setup>Telescope menu and scroll to the Ratios screen

Note the Ratios it has selected for Az and Alt

Now go to Mount menu and select an ETX-125

Go back to the ratios screen and again note the values.

 

Andrew Johansen Melbourne Australia

[Mhanna]

Hi Andrew,

 

The ratios, percentages, and other settings are identical. The only 1 that's different is the focal length (1250 vs. 1900).

 

For both telescope types, it is set to the following.

 

Az/ra 1.36889

Alt/dec 1.3689

Az/ra percent 10%

Az/dec percent 10%

 

Cheers,

Matt

[OzAndrewJ]

Gday Matt

Those ratio numbers are correct for ALL ETX-125 and older model ETX-90s

so there is no way that changing from ETX-90 to ETX-125 should cause what you see.

( Hence my confusion )

I will need to double check what happens when you change models in A4S1

but can you also confirm it didnt think it was polar after changing models.

Thats the only other thing i can think of short term.

 

Andrew Johansen Melbourne Australia

[Mhanna]

Hi Andrew,

 

I took it out again last night and set it up as an ETX 125, and it was fine. I don't know what's going on with it, and it's certainly making me look stupid as I come on here with problems and now magically it's working.

 

I don't know what to say, except that even though the optics are somewhat good, i won't be recommending this scope to the people who are being exposed to this hobby through me.

 

Thanks again for your advice

 

Cheers,

Matt

[OzAndrewJ]

Gday Matt

 

it's certainly making me look stupid

...

i won't be recommending this scope to the people who are being exposed to this hobby through me.

I suspect its the firmware not the mount. I know that changing between polar and AltAz really screws up the later firmware, and this may be what you are seeing when changing model as well.

ie until you reboot with the new settings, they might not reset properly.

The ETX is not "deadly accurate", but the new ETX-125 has a far better gearing system than the old ones and there are lots of them out there working well for the price.

There are also a lot of known bugs in A4S1 hence why i cant recommend using it and have never bothered to try and patch it. For most users, ( esp if you want to use remote control later ), i recommend backloading to a patched A1F7 firmware.

 

Andrew Johansen Melbourne Australia

[EdIII]

QUOTE:

 

There are also a lot of known bugs in A4S1 hence why i cant recommend using it and have never bothered to try and patch it. For most users, ( esp if you want to use remote control later ), i recommend backloading to a patched A1F7 firmware.

 

END-QUOTE:

 

Andrew,

 

How can we identify the patched version of A1F7 or is  A1F7 the patched version?

 

Ed

[OzAndrewJ]

Gday Ed

A1F7 is a version of firmware put out by Meade.

The patch is something i wrote to fix a lot of the known bugs and add some enhancements.

Both files are on the StarPatch site

http://www.stargps.ca/downloads.htm

You use the StarPatch application to import the A1F7 patch file.

Within that are a whole lot of options that you can select/deselect via checkboxes.

When happy, you hit go and StarPatch will modify the base firmware accordingly and load it to the handbox.

 

Andrew Johansen Melbourne Australia

[Mhanna]

Thank you Andrew and all for your help on these issues

[Donuthin]

When setting up my used just purchased ETX 125 FE, the zero marker is at between 8 and 9 if looking at a clock, rather than at the bottom when scope is leveled, is there a way to move the zero to the bottom where it belongs?

[alval]

You just loosen the knob on the arm slightly, that will release the disc, you can then rotate it to the position required then retension the knob. 

Al

[AggedorOfPeladon]

aeair's post helped me a lot, but I still have one odd/annoying problem.  I have an older ETX125 that I bought second hand and it had no hand box, so I bought a new audiostar handbox.  I was able to do an alt/az alignment just fine and it tracks nicely.  The problem is that after a while...I didn't time it but it seems like 30 minutes to an hour...it just goes crazy and starts slewing to crazy coordinates.  I have to power down as it doesn't seem like it's ever going to stop, just grind the gears after hitting the hard stop.  

 

It seems to me that the time when it starts doing this is about the same time the autostar handbox that I have on another ETX125 turns off the screen display.  Still tracking, it just goes into some kind of power saver mode.  I would like to find a way to turn that off and see if it is the problem, but can not see how to do that in the menus or manual.

 

Ideas?

[OzAndrewJ]

Gday AggedorOfPeladon

Its not a menu option you can use

but by simply using the menus, you reset the timer

soooo, just scroll through the menus every 5 mins or so

and it will stay on.

Andrew Johansen Melbourne Australia

[aeajr]

AggedorOfPeladon,

 

My ETX 125 is vintage 2005 with an Autostar controller. My ETX 80 Observer with Audiostar controller is vintage 2018.  I have run both for hours and hours using an external power supply.  I can't imagine what is causing the problem.  But I have never left the hand control untouched for 30 minutes so, who knows. 

 

Sorry but I have no advice.

Edited by aeajr, 25 March 2024 - 08:16 PM.

[Thrifty1]

Does it do this consistently / every time you use it? I’ve had these random slews where it just takes off and I have to cut the power. But it happens very infrequently.