Posts Made By: James Sarte

Just curious, but how does the Synta adjustable refractor cell attach to the optical tube? Is it screwed on? I don't see any attachment points or screws on the cell body itself, so I'm guessing the OTA end is threaded?

I'm having a lot of trouble removing worm mesh backlash and slop from my LXD75's RA axis. No matter what I try, I can't get it right. There is no worm shaft backlash, as I've adjusted the shaft correctly with the brass collar, however the gear mesh problem still remains.

It seems that no matter how I adjust the 3 hex head bolts, along with the two rear attachment bolts of the worm shaft housing, there is always lateral play whenever the axis is rotated East or West. For example, I can adjust all 5 bolts to reduce lateral play when the mount saddle is pointed West. I can spin the aluminum RA worm gear freely, but once the saddle has rotated to the point where its now facing East (rotated 180 degrees), I can feel it begin to bind, and rotation of the aluminum gear becomes difficult.

If I adjust the worm housing so that the aluminum transfer gear spins freely when the saddle is pointed West, and no slop is observed, once the RA axis has reach the polar home position and the saddle starts to rotate towards the East, there is now backlash present.

It almost seems as if the notched cylinder which the worm mates too isn't completely centered within the RA housing, and becomes apparent 180 degrees apart in rotation, or the cylinder itself isn't perfectly circular, rather being slightly oval.

I'm running out of ideas here, and I hope someone can help. If the wprm housing adjustment is left in such a way that the aluminum transfer gear spins freely without binding, there is always some backlash or lateral movement present in the RA axis, and can become highly problematic focusing at high magnification. The image will literal jump up and down in the eyepiece with the movement of the focuser.

Please help! I'm running out patience....

Does anyone know if the motor control box for the Synta CG-5 / Orion SVP would work with the Synscan GOTO for the EQ3-2 mount? They look exactly the same on the outside.

I don't know what happened tonight, but while I was in the middle of doing a 3 star alignment the motor control box started smoking. I shut everything off and brought the mount back inside. I opened the box to find a hole burned right through the DEC control chip soldered onto the board.

To cut a long story short, the DEC no longer functions, but the motor is still ok. The RA control is fine. I plugged the DEC into the RA output of the control box, and the motor still turns. So... not sure what happened, but something caused the DEC control chip to burn out. I did not have any thing reversed or crossed to my knowledge, and the mount was working fine until today.

Here are some pictures of the carnage:


This is a closeup shot of the DEC control chip:

RA control chip is on the left, DEC on the right:

Complete circuit board:

**I'm snipping this from my post on the LX200GPS Yahoo group. Hopefully though, someone here can also provide some insight.

I posted several days ago about having a lot of trouble achieving fine collimation with a new LX200R. Unfortunately, I did not get a response from this group.

Just to recap; for example if I collimate with a diagonal and the CO is down and to the left on outside of focus, it will be down and to the right on inside of focus. No matter how much I try to center one side, it will be off on the other. I've tried this with three different diagonals.

I also tried collimating with no diagonal, just an EP inserted directly into the visual back. I was able (at least to my eye) get the diffraction rings concentric on both sides of focus. This leads me to believe that perhaps all 3 of my diagonals may be bad. I find that hard to believe though.

After collimating with just an EP and no diagonal, I looked at the front of the telescope to see how well the reflections lined up. They looked a little off, especially the reflection of the secondary mirror housing or baffle. For example, if I aligned my eye so that the center reflections are even, the outermost reflection in the mirror seemed skewed. If I repositioned my eye so that the outermost rings reflections were concentric, then the interior reflection of the secondary seemed skewed.

This brings me to a small experiment I tried last night. I stuck a flash light into the visual back of the OTA and looked at the light and shadow projection on a wall. The shadow of the secondary housing is off-centered.

Now my question is this: would an off-axis secondary cause my collimation issues with a diagonal? Would an off-axis secondary also introduce optical aberrations?

I know that the 6-screw secondary can be removed without touching the corrector. How then can I reposition it so that it is fully centered on the corrector?

Please help, as I'd really like to avoid sending this back to Meade.

Best regards,
James

That is an excellent way to put it Bill. Thanks, you have set my mind at ease.

What is the base and fork made out of? Is it ABS plastic, or some kind of metal?

Nice scope BTW! Hope you enjoy it.

I've heard good things about them from Mark over at Digitec Optical. He carries a full line of Sac camera's.

That's a mighty nice goose you got there. ;-)

WOW! All I have to say is that is beautiful craftsmanship. Maybe you could start custom building those for other Astromarters.

Hi Josh, I'm new to this hobby too so I may not be able to give you much useful information. I do want to ask you though what you primarily intend to use the scope for, i.e. DSO, planets or astrophotography?

As for the Skyview Pro 127 Maksutov, I've seen it in person. It looks very nice with no plastic anywhere. The mount is also beefy enough in my opinion to handle the weight of the 127 which is negligible compared to others. I do recommend that if you go for that, get the polar alignment scope and dual axis motors for a few bucks more.

From what everyone has told me, you can't really go wrong with Orion products to start with. Their customer service is top-notch.

Cheers!

James