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Review - Meade Instruments ETX-125 Observer Telescope

Posted: 24 May 2017


ETX-125 Observer Telescope
Meade Instruments

After launching "Weasner's Mighty ETX Site" in 1996 I quickly became known as "Mr. ETX". Although I stopped updating the Site in 2013, it still remains a goto source for ETX users around the world. After purchasing my first ETX (now known as the ETX-90RA) in 1996 and with my continued commitment to the ETX via the web site and other activities, Meade provided me with some newer ETX models over the years: a loaner ETX-90AT in 1999, the ETX-125AT in 2000, the ETX-70AT in 2001, the ETX-105PE in 2005, and an ETX-LS 6" ACF that was briefly on loan in 2009. As I have reported many times on my Cassiopeia Observatory reports, I have continued to use the ETX-70/90/105/125 telescopes at various times from my observatory site and at star parties. My ETX telescopes remain cherished possessions and are still a joy to use. So it was with considerable excitement that I learned that Meade wanted to send me the newest ETX-125 Observer telescope. It arrived in early May 2017.

First, lets get the specs out of the way:

   127mm, f/15, 1900mm Focal Length, Maksutov-Cassegrain
   1.25" 26mm (73X) and 9.7mm (196X) Super Plossl Eyepieces
   Internal 90° Degree Diagonal
   Internal Flip Mirror System
   1X Red Dot Viewfinder
   Fork Mount with DC Servo Motors
   Full Size Steel Adjustable Height Tripod with EQ Tilt Plate
   AudioStar controller containing over 30,000 Celestial Objects
   Telescope weight 15 pounds, Tripod weight 9.7 pounds
   Powered by 8 1.5V AA Batteries or a 12VDC External Power Supply (neither included)

Many of these specifications are the same as the original ETX-125 model from 1999. There have been some changes for the better over the years as newer ETX-125 models were shipped. The ETX-125 model was discontinued for awhile, but amateur astronomers should be happy that it has now returned.

Unboxing and Set Up

The day after the new ETX-125 arrived I unboxed it in front of my observatory.


As a highly experienced ETX user I decided to not read the manual before setting up the telescope. I figured I knew what I was doing. I still recommend that first time ETX owners read the manual a couple of times before unboxing and setting up the telescope. These steps, as well as learning how to use the telescope (any telescope), should be done in the daytime when you can see what you are doing and what the telescope is doing. Get comfortable using the telescope in the light, then you can start using the telescope in the dark.

I was pleased to see that the ETX legacy was honored on the box:


All of the ETX-125 Observer telescope components are well packed inside the single container:


Here is the ETX-125 set up in the Altitude/Azimuth mounting mode:


Here is the ETX-125 set up in the Polar mounting mode, with the aperture cover removed:


There were some things I noted during the set up as being different from my previous ETX telescopes.

A 1.25" bubble level and compass was included, as well as a 1.25" 9.7mm Super Plössl eyepiece, along with the standard 1.25" 26mm Super Plössl eyepiece:


Unlike what is shown in the manual, the telescope mounting bolts on the tripod base have been rotated 90° from their position on the older #884 tripod to make access easier without needing to raise the tilt-plate:


The aperture cover now has tension clips (similar to camera lens caps) to securely hold it to the telescope tube.

The AudioStar has an included hook to hang the handcontroller on the tripod, and unlike the AutoStar, there is a speaker on the back:


I initially had some difficulty getting the hook fully inserted; one side refused to go into the slot (as seen in the photo above). Once I got the ends aligned it went in fine.

The keys on the AudioStar are now blue (vs black ones on the AutoStar handcontrollers):


The battery access compartment is on top of the base, meaning the telescope does not have to be removed from the tripod to change batteries, and the Azimuth/RA lock is now a knob vs the previous lever (which is still shown in the manual):


The HBX port, power switch & LED, AUX ports, and 12V input jack are now on the fork arm and rotate with the telescope, so there are no more "hard stops" as with the case with the original ETX-125 model:


The ETX-125 Observer telescope is essentially the same size as the original ETX-125 model from 1999. The only real difference that might matter to some users (i.e., for dew heaters, solar filters, etc.) is the slight difference in the OTA diameter. The ETX-125AT is 149mm in diameter and the ETX-125 Observer is 146mm. The ETX-125AT telescope weighed 15.2 lbs and the ETX-125 Observer weighes 15 lbs, not including their tripods. The adjustable height tripod allows for using the telescope sitting down or standing up. I normally use my ETX telescopes while sitting down, so did not extend the tripod legs.

Unboxing and setup took about 1 hour, but I was taking photographs as I did each step.

The Manual

After setting up the telescope I returned to the house to read through the manual. As all of my other ETX and (LX200-ACF and LX600) telescopes use a non-audio AutoStar handcontroller, I wanted to learn about using the AudioStar handcontroller that comes with currently shipping ETX-80, ETX-90, and ETX-125 Observer Series telescopes. The big difference with the AudioStar vs the older AutoStar #497 is the addition of Meade's Astronomer Inside with audio content for over 500 objects. For those new to viewing the night sky and the objects visible in a telescope, these audio descriptions will be fun and educational. For experienced amateur astronomers the audio content will likely not be needed and can be turned off. Surprisingly however, the manual does NOT describe how to actually use the Astronomer Inside and turn on/off the audio content! That discovery is left to the user (but I'll tell you how in the "First Light" section on page 2 of this review).

The manual mentions that the ETX-80 and ETX-90 optical tube assembly (OTA) can be removed from the fork arms for mounting on a camera tripod. The manual says that the ETX-125 OTA can NOT be removed from the fork arms, but there are two tripod attachment holes on the bottom of the ETX-125 OTA (seen in the photo above showing the battery compartment and Azimuth/RA lock knob). I suspect that like the original model ETXes, the ETX-125 Observer OTA can be unmounted from the fork arms by removing four setscrews. However, most users will never need to remove the OTA from the fork arms.

In Alt/Az mounting mode the AudioStar can align on either True North or Magnetic North (the AutoStar only used True North). So even when the sky is still too bright to see the North Star Polaris or it is hidden by an obstruction, you can still begin the alignment process by using the supplied magnetic compass and selecting Magnetic North on the AudioStar. The Alt/Az "home position" is correctly shown in Figure 1 in the manual. When mounting in Equatorial (Polar) mode the manual (Appendix D) is less clear about the "home position". Two figures (28 and 29) both show positions for "polar alignment" but the captions are the same in both figures. And neither figure is described as the Polar "Home Position". Figure 29 shows the correct position. Appendix D does not explicitly state that the AudioStar needs to be changed from Alt/Az to Polar in the Setup > Telescope > Mount menu, so be certain to do that when mounting in polar mode.

The manual notes that the ETX-90 has an "internal time chip" and so will know the date and time on first power up. Of course, that would need to be corrected for your location. Surprisingly, there is no such time chip in the newer ETX-125 model; I had to input the current date and time on each power-up.

The manual includes a brief discussion of the rear "photo port" on the ETX models, which has been on every ETX model since 1996. It says this is where you attach a "35mm camera". Hey Meade, it is past time to update the manual to remove the references to a 35mm camera! Anyone still using 35mm cameras?

If you are familiar with the menu structure and using AutoStar handcontrollers, you will feel right at home with the AudioStar. And, as is the case with the AutoStar handcontrollers, learning to navigate the menu structure is easy and logical.

The ETX-80/90/125 Observer Series manual is available online from

The ETX-125 Observer telescope includes a DVD to install the AutoStar Suite application (for Microsoft Windows only). The AutoStar Suite provides additional functionality and control of the ETX using a RS-232 serial (not USB) connection from a computer. However, the needed #505 serial cable is not included with the telescope so users will have to purchase that separately. Many of today's telescope buyers may not even use a computer, instead only using a smartphone or tablet device for their everyday needs. For those users Meade sells the Stella Wi-Fi Adapter ($199) and the Stella Access app for Android and iOS devices ($15). Other Wi-Fi adapters and apps may also be compatible (see "Wi-Fi Adapter Control" on page 2 of this review).

Go to Page 2 (First Light, Alt/Az Mounting Mode, Polar Mounting, Wi-Fi Adapter Control)

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