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Another defective CGEM?

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#1 bdawg6381

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Posted 15 January 2010 - 10:55 AM

I've searched through various CGEM problems on CN and on the Yahoo tech forums and mine are similar to some on both but overall not similar in all aspects. I ordered the mount from XX telescope company and was recieved several days later via UPS.

The usual damage was seen on the boxes, nothing out of the ordinary however the CD that came with the mount that had the nexremote software was cracked and unusable. Everything else seemed well packaged when opened with no signs of damage.

Unfortunately I had no way of mounting my refractor on the CGEM saddle and had ordered a D series dovetail for just that reason. Last night was the first night that I had all of the required components to test out the mount.

My prior experience with go-to style mounts was an EQ5Pro and I sold/upgraded to the CGEM in order to carry a heavier astrophotography payload. I consider my self, not an expert, but well experienced with the EQ5Pro including drift alignment and knowledge of all the menu functions.

So now you have some background... to the meat of the problems:

I set up the mount/telescope (with illuminated reticle eyepiece in telescope) on my back patio powered by a 17AH 12V "Die Hard" portable power source (proven on various occasions to work very well with a myriad of astro/non-astro equipment). I had previously set the lat/long and tried the telescope out briefly inside just to check basic functions.

When positioning the telescope I made sure that the polar finder "hole" had the NS centered to get a rough position on polar alignment. Next I turned the telescope ON, input the time/date/etc. and began to perform the alignment.

First star I chose was one of the Pegasus square in the west. It seemed to slew to it but:

Problem #1: The "spinning bar" on the right side of the controller display never stopped and the controller never told me to begin centering star with keypad. The movement in RA stopped but the Dec axis continued moving after several seconds. It would move either 45 or 90 degrees -- stop for 5 secs or so -- and continue moving -- stop -- move -- and keep moving in a counterclockwise direction (if facing south) spinning without end!

I could stop the movement of the Dec if I tapped one of the directional keys and then the message to align star with directional buttons came up... OK so I did this - however its VERY hard to align a star when:

Problem #2 - my "RATE" button only seems to effect my RA axis, the Dec axis always slews at maximum speed regardless of my rate setting (talk about frustrating).

So... even with the RA rate on "9" all the time (even though it indicates its at 3, 5, 7 etc - whatever I had set it at) I managed to perform a 2-star alignment that showed up as "successful" on the handcontroller.

OK... supposing it was successful lets try to "go-to" something. I chose an easy target, M42, that was in the south east at the time.

Now Problem #1 rears its head again except during the go-to slew instead of an alignment slew (the RA stops but the Dec just keeps spinning).

This particular CGEM has the saddle tightening knobs on the west side with the index marks all on the south side (viewing the Yahoo forums apparently the position of these is a crpshoot and both configurations have worked OK -- just weird to me that they would change these around randomly).

For troubleshooting I've tried resetting the controller to factory settings and have also varied my power sources with different portable and hardline 12V sources I have available.

So... after doing some research my best guess is that I have a defective mount must likely due to something in the Dec motor or motor control wiring. I sent a message to XX company today to hopefully replace it. I'll keep you updated.

Just wanted to post this incase anyone else is having similar problems with theirs in the future. I'm also welcome to any input/suggestions you may have! :help:

#2 jrcrilly

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Posted 15 January 2010 - 11:19 AM

So... after doing some research my best guess is that I have a LEMON must likely due to something in the Dec motor or motor control wiring.


The DEC encoder isn't being read properly. What you describe is typical open loop behavior.

For the record: a lemon is a device that still exhibits the same problem(s) after three unsuccessful repair attempts by the seller. What you have is a defective mount. It could possibly turn out to be a lemon in the end, of course - but it can't be one yet, as no repair attempts have been made.

#3 John J

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Posted 15 January 2010 - 11:22 AM

bdawg6381
I just finished rebuilding a club members CG5 AGT. He was having similar problems with his Dec axis. The Dec would just keep going some times on a goto. I found that the RJ12 connector on the hand control was not crimped properly. His mount is way past warranty so I replaced the connector. The 6 wire connectors and crimping tool can be found at any Ace hardware store. It's an easy fix and if it doesn't work I don't think they would notice if you had to send it back for repair.
JJ

#4 bdawg6381

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Posted 15 January 2010 - 11:25 AM

So... after doing some research my best guess is that I have a LEMON must likely due to something in the Dec motor or motor control wiring.


The DEC encoder isn't being read properly. What you describe is typical open loop behavior.

For the record: a lemon is a device that still exhibits the same problem(s) after three unsuccessful repair attempts by the seller. What you have is a defective mount. It could possibly turn out to be a lemon in the end, of course - but it can't be one yet, as no repair attempts have been made.


Updated to defective - thanks for the catch

#5 bdawg6381

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Posted 15 January 2010 - 11:50 AM

Will reveal company now... I'm working with High Point Scientific. Called them and they are shipping me a new head TODAY! They said call them back after I try the new head out and then they will call UPS to pick up the old one. Now THAT is customer service! They definitely just won my future business (and it helps they are east coast too). They said they've heard of these issues before and that it is a Celestron QC problem. I'll post updates next week after receipt of new mount head.

#6 nemo129

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Posted 15 January 2010 - 01:44 PM

Brandon,
Yes, please keep us posted. I have a CGEM showing up today from HPS, and I have no where near your experience with Celestron GoTo mounts. I am starting to get a little worried :( about several recent posts from CN forum members about issues with CGEMs.
Thanks for your observations.

Clear Skies,
Kirk

#7 t.r.

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Posted 22 January 2010 - 10:32 AM

I will second High Point Scientifics service, sent back a C-6, they picked up the tab and arranged shipping, replacement sent in a day!!! I was floored! A+ Customer Service=Customer Satisfaction!

#8 nemo129

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Posted 22 January 2010 - 12:14 PM

Tim,
Thanks for the reassurance. I got my CGEM, and it has performed admirably in two outings so far. I really do like dealing with HPS, they were honest, knowledgeable and very professional. I also like the fact that they are in NJ, so I am in the next day delivery zone for UPS. :jump:
Kirk

#9 Joe Lalumia

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Posted 23 January 2010 - 11:46 AM

High Point is a VERY good vendor! So the new mount works just fine.........problem solved!

#10 bdawg6381

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Posted 23 January 2010 - 02:31 PM

Recieved the new head OK on the Tuesday after they shipped it the Friday before (not bad turn around since I had called them on that Friday!). Since then the weather has been dismal and I haven't taken it out of the house. From the "mock" runs I have done with the new head in the house though it seems like the replacement one works well. I called HPS and let them know that the new one seemed to work but they weren't satisfied until I could take it out under the actual stars. Only then they said would they send someone back to pick up the old one -- after they were 100% sure I was satisfied. Great customer service!!






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