Installation Guide of Telescope Drive Master

Encoder-adapter for 10" LX200 Classic mount

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 "old fashioned" LX200 Classic 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", depending on Jumper adjustments, see TDM User's Guide) within 95% of your exposure time if you use 0.5x sidereal speed (or lower) as guiding correction speed during tracking. If you use the original Autostar controller (old version) with 1x fixed sidereal speed as guide correction speed, TDM control range will be a bit higher but less than ±2". It means your mount will became one of the best tracking ability mounts among amateur and semipro equatorial mounts all over the world (even if your dome-shutter is closed...).

To achieve this unbelievable result, 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 http://www.telescopedrivemaster.com/ website's documents.

TDM system contains two main logical units or parts: a high precision encoder unit (encoder, coupling and mount-dependent mechanical adaptor) attached directly onto the RA shaft of the mount and an electronic device (a sort of "black-box" with connectors, cables and power supply), 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 adaptor and encoder installation only.

Before starting, it is highly important to emphasize that both encoder unit and its adaptor 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 a set of Allen-wrenches, a few open-ended wrenches and a Torch screwdriver (size T8 or T9) will be needed for installation.

As you got your package, you need to find the coupling mounted onto the encoder as seen below. This is a high accuracy, temperature compensated coupling developed by MDA-TelesCoop especially for this type of encoder and for this purpose. Two of the eight flat-spring fixing screws are black; the rest of them are shiny stainless steel. Additionally, you will find six pieces of small stainless steel screws and the parts of the adaptor (stainless steel encoder shaft, aluminum stator plate and black anodized aluminum cover together with cap).

Before assembling parts during installation, please always check and clean the threads and surfaces of the RA shaft and casting-house 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 surfaces and threads of the parts if it is necessary. Only clean and tight mechanical contacts between surfaces will provide correct mechanical coupling and positions.

Step 1:

After fixing telescope shafts, please remove the flat black cover of the RA shaft from between the forks (using Allen-wrench). You will need these two screws later so please put them away to good place.

Step 2:

Please unscrew the central fixing bolt from the RA shaft and also move the shiny thrust washer away.

Step 3:

Next step is attaching encoder shaft onto the top of the RA haft. Do not touch the long cylindrical surface of the encoder shaft with any metal tool (e.g. pliers)!!! You have to be able to screw encoder shaft gently into the RA shaft manually. Only the last half or one rotation of the encoder shaft needs an open-ended wrench (size 8) to fix it well. This part cannot have any offset (coning and/or eccentricity) compared to the RA axis!!!

Step 4:

Please release expanding female screws of the stator plate if they are spanned and, according to the picture below, put the stator plate into its place in the fork-casting. There is no upper or lower side; orientation is not relevant issue. But you need to push this part completely down to the bottom of this small chamber.

Step 5:

Now, push the encoder gently but completely (until "click") onto the shaft by hand.

Important: before you do it, please release every screw (8pcs) of the flat springs round about the shaft simultaneously just a little bit and, while pushing the coupling parts onto each other by hand, fix them again. (See the explanation of the coupling among installation guides on the http://www.telescopedrivemaster.com/ website.)

Step 6:

In this pressed down situation, please fix the upper ring clamp of the encoder well enough using a Torch screw driver (size T8 or T9).

Step 7:

You must release the shaft (with the previously used open-end wrench again) and carefully remove it from the RA shaft completely together with the encoder which has been fixed on it.

Step 8:

Please remove two black screws from the coupling and remove the front part of the coupling. Use Allen-wrench to do it.

Step 9:

Now, please tighten the front side clamping ring of the encoder as well via any holes of the flat springs using Torch screw (size T8 or T9). You can reach the screw on the front side clamp via any of the elongated holes created especially for this purpose on the flat spring. Please stop shaft rotation by your finger; in this way it is much easier to fix the screw.

Step 10:

You need to assemble the front part of the coupling onto the stator plate. Please use four pieces of stainless steel screws attached. Its orientation is important, be careful: two small lugs have to be in the position shown in the picture (towards expanding female screws of the stator plate).

Step 11:

Please fit the coupling together again using shiny stainless steel screws provided with the encoder instead of the original black ones. Again, it is important to ensure the close contact of the coupling parts as it was described in the step 5 above !!!

Step 12:

Carefully, screw the whole preassembled encoder unit back into the RA shaft's central thread. You can start it grabbing the clamping ring by hand and tighten it gently but well enough using a wrench.

Step 13:

Finally, you need to fix the stator plate using its two expanding female screws. It is very important to expand them well to provide absolutely fixed and backlash-free operation.

Step 14:

The main parts of the encoder adapter have been installed so far. Now, please put the cover of the encoder to the place of the original flat cover and fix it using the same two screws dismounted as the very first step of this installation process. You will find a gap on the cylinder provided for the encoder cable.

Step 15:

Finally, please install the cover-cap for saving encoder against environmental influences.

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

This encoder position results roughly 10° dead zone in declination around celestial pole if you use extra long back-focus accessories without diagonal but normally there is enough space, for instance, to use a DSI III camera around Polaris as well (see above).

Now, you just need to create cable connections among the electric units of the telescope 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 http://www.telescopedrivemaster.com/ website.