ETX ON LXD75 MOUNT Last updated: 9 October 2006

Subject:	ETX125 on LXD75 mount
Sent:	Sunday, September 17, 2006 14:04:02
From:	spunkyk98 (spunkyk98@wi.rr.com)
just thought I send you a pic of my ETX-125EC mounted on an LXD75 mount.
When funds become available, I plan on mounting a 8" OTA to the LXD75
mount.  For the time being, I put my ETX-125 on the mount.  I had to
modify one of the dove tail holes to match the mounting holes on the
bottom of the ETX125 OTA.

I bought the LXD75 mount used with a dove tail bracket, a autostar #497,
a battery pack and couple of weights. The mount tracks beautifully! It
can hold an image in a 26mm eyepiece for hours. I tested out my Nikon
D70 mounted to the top of the OTA and I got some nice pics but when I
zoom in on those pics, I can see I didn't have the camera well focused.
So I'll be doing some more D70 mounted pics in the future. I want to
test out using the D70 at prime focus as well.  Right now, the mount can
easily hold an image for more than 2 minutes for astro pics without star
trailing.

I used a DSI-c connected the EXT125 and was amazed that I didn't have to
fight trying to keep the image centered in Envisage.

The only problem I really encountered was when I tried to train the
drives. The AZ/RA slewed the scope, but re-centered the object I was
training on. So I could not train on that axis. The ALT/DEC training
worked as I expected. Not really sure what's up with that. The tracking
is unbelievable as it is right now. But, I can't help to think I may
have something wrong with the setup. The scope is balanced on both axis.

Here's what the ETX-125 looks like mounted on an LXD75 mount:



I have seen some posts on your site regarding mounting an ETX125 OTA on
a LXD75 mount, so I thought I would post this.
 
Thanks,
Kevin 

And:

Well, as a matter of fact, I loaded up the latest Autostar software and
patch43aa. Then did a RESET/CALIBRATE MOTORS/TRAIN DRIVES I think, but I
don't remember now with all the excitement of the new mount.

I'll will retry the drive training, and I want to go thru the LXD55/75
ADJUST training while we have cloudy weather here. As soon as I turn on
the telescope now, I usually do a CALIBRATE MOTORS because I'm usually
not sure if I last used the battery pack. So, hopefully that's what I
forgot to do the first time I turned on the Autostar after updating the
rom.

Thanks for the help, I'll let you know how it works out.
Kevin

Subject:	Re: ETX125 on LXD75 mount update
Sent:	Sunday, October 8, 2006 21:19:55
From:	spunkyk98 (spunkyk98@wi.rr.com)
LXD75 mount...

I did a RESET/CALIBRATE MOTORS/TRAIN DRIVES, during the RA training, the
scope slewed, but the target I used for training was very close to
center, and does this for both directions. For the DEC training, the
scope slews to just outside of the field of view for both directions
during training.

I took off the motor houses, and I noticed the DEC motor decoder wheel
was bent! The RA decoder appears to be just fine. Don't know how the
wheel gets bent, I haven't crashed the motors into the mount at all. I
did buy the mount used, so it could have already been bent. I used a
trick from LXD75.com, I colored the RA encoder wheel flat black on both
sides. The mount moves as smoothly in RA as it does in DEC. And the worm
gears turn smooth on both axis. I did another RESET/CALIBRATE
MOTORS/TRAIN DRIVES, the RA training was the same as I stated above. 
After the first alignment star, the goto's are almost perfect! The
tracking is still very good.

I noticed now with the battery pack connected and fresh batteries, the
RA motor tends to make a whinning when it's slewing like it's not
getting a constant rate of power. When the AC adapter is connected, it
is not as noticable. The DEC motor sounds fine on both batteries and AC
power. I'll probably just leave it for now, until I get a 8" OTA to
mount on it, and see how it performs.

Thanks for the help,
Kevin

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