for Losmandy G11

Installation Guide of Telescope Drive Master

Encoder-adapter for Losmandy G11 mount

 

Please start with reading this important message below!!!

I have made this installation guide below, together with taking demo-pictures, using the original Heidenhain-type, locating pin based encoder coupling. But, during continuous product development process, I replaced it by the new, much more accurate coupling-version.

Obsolete coupling:

http://mda-telescoop.com/index.php?option=com_content&view=article&id=58&Itemid=88

New coupling:

http://mda-telescoop.com/index.php?option=com_content&view=article&id=63&Itemid=98

Unfortunately, I do not have a chance to correct the old pictures and the relevant parts of this installation guide because this telescope mount is not in my observatory nowadays. So please ignore the instructions of the pin-based coupling installation here and, instead of these points, use the description of the new coupling installation guide based on the page above. The rest of the adapter installation process has remained the same.

At the same time, if you need any additional help regarding this issue, please do not hesitate to write me to my e-mail address which can be found on the Contact page within Company Details.

 

First of all, thank you very much for purchasing our product called "Telescope Drive Master" and congratulation for your decision. This system will improve the tracking accuracy of your G11 equatorial mount dramatically independently from its original periodic error amplitude because both periodic and aperiodic errors of your mount will completely be eliminated using our real time, ultra high precision correction system, without using conventional autoguider. We guarantee that your tracking error will remain within 1" (one arc-second) range total (or ±0.5") within 95% of your exposure time. It means your mount will have the best tracking ability among the amateur and semipro equatorial mounts all over the world (even if your dome-shutter is closed...).

To achieve this unbelievable result, before the installation of your Telescope Drive Master, you need to complete a very accurate polar alignment process of course. Please find our proposed method to do that on the companion CD ROM or among www.telescopedrivemaster.com website's documents.

TDM controlling system contains two main logical units or parts: a high precision encoder unit (encoder and its mechanical adapter) attached directly onto the RA shaft of the mount and an electronic device (a sort of "black-box" with connectors), which receives the electrical signals arriving from the encoder unit and sends control instructions to the mount's driver via its auto-guider input connector. So you will need to install the mechanical elements and the electronic device as well but do not worry: both of them can be done very easily.

Please find the drawing and description of electronic connections to be set in relevant part of User's Guide because this schematic is the same for every telescope mount. In this document you will find the mount specific instructions for mechanical adapter and encoder installation only.

Before starting it is highly important to emphasize that both encoder unit and its adapter elements are sensitive mechanical parts!!! Do not drop any of them; do not stress them during installation!!! Handle with care! Any damages of these parts can destroy product's accuracy.

Just two Allen-wrenches (in size 2mm and 3mm), a Torch screwdriver (size#T9), some metal glue (e.g. Loctite) and a small hammer will be needed for installation.

You need to find a small plastic bag within encoder box with small particles as seen below.

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Mechanical parts of the adapter have been assembled in one unit before delivery. The risk of any mechanical damage during transportation is much lower in this way but, it means, you need to disassemble them before installation. You just need to remove those screws (4 pcs; use 2mm Allen-wrench) which fix the cover of the encoder unit onto the adapter stator as you can see below. Do NOT remove those 6 (2x3) pcs screws which keep all the three parts of the stator in one unit!!!

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Before assembling parts during installation, please always check and clean all of the threads and surfaces of the lower end of the RA shaft and encoder adaptor elements if necessary. Use clean clothes (not nylon!) for smooth surfaces and a dry toothbrush to clean the internal and/or external thread(s) of the RA hollow shaft if it is necessary. Only the clean and tight mechanical contact between surfaces will provide correct mechanical coupling and positions.

Step 1:

At first, please rotate RA shaft in neutral position where your mount can be stabile without fixing. Remove the brake-ring from the RA-shaft.

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Step 2:

Using a small hand-hammer if it is necessary (but applying just small knocks), put the attached tiny locating pin into the hole (see picture below). The length of the pin remained out of the stator ring has to be between 12 and 14 mm roughly. Do not enlarge the diameter of the hole!!! Thanks to the tight fit, the pin has to be fixed without any slackness!!! To ensure correct and the most rigid position of locating pin or if you removed it from the hole (which is not recommended), and want to put it back again but the hole is not tight enough, please use some metal glue (e.g. Loctite) for fixing locating pin. If this pin can move just an extremely little bit then TDM will not work properly!!!

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Step 3:

Now, put the stator onto the house of the RA shaft and fix its position tightening six set-screws (2x3 pcs on both sides, with 2mm Allen-wrench) pre-installed into their holes. If you have new type of G11 mount you need to change the large diameter spacer ring to the small one (which has the same diameter as the old version has) provided in adapter package during this action (it can be seen above, in the 2nd picture of this document). Also, you need to screw the original RA brake-ring back to the RA shaft in this step. Draw the fixing screws of the stator on very well please. Do not worry: a pre-installed plastic ring will save the surface of your mount but, at the same time, the stator has to be fixed rigidly enough.

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Step 4:

Next step is attaching encoder shaft into the hollow shaft of RA axis. Do NOT touch the long cylindrical surface of the encoder shaft with any metal tool (e.g. pliers)!!! Just push this part into the (internally cleaned) hollow shaft completely and fix it using a 3mm Allen wrench on coaxial expansion screw as you see below in the picture. Tighten it well enough, please. This part cannot have any position offset or slip compared to the RA axis movement; it has to become an integral part of the RA shaft!

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Step 5:

Please install black plastic bucket into the encoder slot. It has to glide to its place firmly. Please find possible versions of encoder installation in the file called "Heidenhain.jpg": version 3 has to be applied for this type of adapter.

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Step 6:

Now, please check the released clamps on both the front and back side of the encoder and push the encoder firmly onto the previously installed and cleaned steel shaft. The position of the glued locating pin has to fit to the plastic bucket. The diameter of the locating pin is a bit larger than the slot in the plastic bucket so you need to push it a bit harder. Avoiding stator deformation during this action, it is useful to keep against this force from the backside of the stator by hand (see picture below). But be careful: roughly 1mm gap has to remain between the surface of the stator back side and the encoder front side.

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Step 7:

Using Torch screw (size#T9) tighten two screws well in the clamping ring on both ends of the encoder. You can reach the screw on the front side via slots created especially for this purpose onto the encoder body.

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Step 8:

The main parts of the encoder adapter have been installed so far. Now, please put the cover of the encoder to its place and fix it in proper position (cable slot is down) using the same screws dismounted as the very first step of this installation process. (A small difference in the position of the encoder and cover is not a problem; just push the cable into the empty space between the encoder and its cover.)

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Step 9:

Finally, please put the cover-cap to the RA shaft for saving encoder against environmental influences.

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Congratulation, you successfully installed the encoder onto your equatorial mount and you have finished the most difficult part of the installation process!!!

You just need to create cable connections among telescope electric units according to the relevant part of the User's Guide.

Additionally, please find several useful tips and tricks in the User's Guide of TDM and other documents found on companion CD ROM or visiting www.telescopedrivemaster.com website.

 
original solarflare design by rhuk
modified by MDA-TelesCoop