My MEADE ETX 105 has/was broken, horizontal drive.

My English is strange I think ;-), but I have never ever learned it .. just used it ... I hope the pictures can tell my story ...

After about a few years not to have been activated, I decided that now I have to go and enjoy this lovely astronomical device, that the thought such done ...

Well, I'll have to go through both training and alignment and what else should be refreshed, including my own memory, about how it was working. I have at some time back installed some software so the binoculars computer (#497) at startup asking for a GPS, and if it is there, it reads date - time and place, now that was the first ups, according to this old Garmin GPS, I was in 2094 in November (2018 July) so it did not work anymore ... but it became a lot worse :-(

But I also have a super good Garmin GPSmap 60csx which, according to the manual, also has output and input for NMEA GPS data, of course, the old GPS to ETX cable did not fit, but I found one on nights with all four wires led to the low cost of 300,00 DKK incl. Postage ... (but would it work?) Found a 25 pole rs232 female jacket molded in plastic straight legs and warmed with my soldering iron and pulled a pair of connectors ... fits perfectly over the male jacks of the GPS so I made a cable…

GPS data 1         GPS data 2

And it works, my MEADE ETX 105 #497 retrieves again GPS data at start-up with exact date - time - place.

After entering the correct data for time and place, my MEADE ETX 105 started its star alignment procedure, it went well sometimes and I also began to remember how to use my MEADE ETX 105 ;-) and then disaster struck, suddenly my MEADE ETX 105 would only drive the optics, it drove slightly over the top in vertical motion, there was no sideways (horizontal) motion.

In manual testing, I found that the vertical movement worked but not the horizontal.


ETX 01

At first I thought it was just the free floating plug, that had jump off, but it turned out that there was a connection between the gearbox and the winding drive, that was broken and pushed the plug off. Now are good advice expensive ;-)

I had to go into the closet and find my ‘Gyro Gearloose hat ...' who said: It might be done with a few clips a little bit of Araldite and some frenzy - The last statement of dexterity was not exaggerated ... ;-)

ETX 03

 Here's a picture of the broken connection between the gearbox and the wreckage, a possible reason may be that the black ring around the white shaft / connection went a little tight and lacked grease  ... I have shredded fine sandpaper with the shaft between the sprocket and quite a little, but then the black ring now runs lightly when the sprocket is running and lubricates with anhydrous grease.

ETX parts

The gearbox and the wrecked out, the black plastic ring on the white shaft at the end of the screw, the load cling to the gearbox :-(

  Here, my ‘Gyro Gearloose hat ...' came up with the idea that there could be a couple of clips, then I drilled two holes in the Gearbox section and two exactly customized holes in the winding section, and as shown in the picture below, sticks I two clips through (for the sake of illustration you can still see that there are clips)

ETX 05

and the picture below shows that the two sides have been pushed together and it can be seen that the two clips continue to wreck the party (for the sake of illustration, the parties have not pushed all the way)

ETX 07

As can be seen, one of the three mounting eyes is also broken.

ETX 08b

On the picture above, see how to bend the clips to the bake and make a small angle to get caught in the wreck, in a small hole.

ETX 08c

It is all glued to Araldite, (I used a match like a spartel ;-)) to keep it all in place, while Araldite hardeners put aside a hanger to hold the small tap down the hole.

ETX 09

Så var der også et problem med dette øje… der sammen med to andre fæstnings øjne skal holde gearkassen på plads. Det viste sig at skaden var større end det umidelbart ses her, på næste billede ses hvorfor jeg måtte ofre en klips mere på projektet ;-)

ETX 10

Again, two holes were drilled and a clip was adapted.


ETX 13

Here is the finished result.


27-jul 2018 Benny

My MEADE ETX 105 was then reunited with gear and wreckage, and I made a test with the locking pole switched off with an external power supply that I put to the wire that goes from the board printing board (ie only with the motor to the device not to control the electronics) the external power supply I used can be controlled from 0 to 5 volts, i started with 0 volts and screwed up and at about 1.5 / 2.0 volts drove gerkasse and sneak as mentioned in free gear... as seen on the video.

Then I put the baseplate on and was ready for the right test, I chose to do this test in full daylight on my porch table ... I am aware that after separating and reassembling again I would go through all line up procedures in order to expect a reasonable pressure of the Go To function ... but first I was interested if I had a MEADE ETX 105 that could move both horizontally and vertically, with something similar to 'Go To' functionality, I used my iPad and an astronomy The APP SkyView to find the approximate viewing position of the two guided stars my MEADE ETX 105 had chosen and it turned out that my MEADE ETX 105 and iPad agreed with the direction and height I tried with a couple of other stars in other directions with the same result, and ended with Venus, that also looked right ... this could well be called a blind test because I could not see the chosen celestial bodies.

Men fra at have en MEADE ETX 105 der kun kunne flytte optikken i vertikalt plan hvilket var ikke brugbart… har jeg nu en MEADE ETX 105 der bevæge sig både horionsalt og vertikalt, om min Georg gearløse reparation er holdbar, vil kun tiden vise…

But now I have get the precision back in my MEADE ETX 105, so I have to look about my investment in three clips and a little Araldite was right ;-)

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