Installation Guide of Telescope Drive Master

Encoder-adapter for Paramount ME mounts

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 originally very good tracking accuracy of your Paramount ME equatorial mount to sub-arc-second range 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 2” (two arc-second) range ptv (peek-to-valley, which is ±1” compared to zero) or less (average is ±0.7”) within 95% of your exposure time.

(Please see Mr. Jerry Hubbell’s test report:

http://mda-telescoop.com/images/stories/downloads/tdm_control_investigation.pdf)

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 very nice 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 Allen-wrenches and a Torch screwdriver (size#T9) will be needed for adapter-installation.

The encoder (Heidenhain ERN180 type) and mechanical parts of the adapter can be found in the picture below. Please do not release the screws at the edges of the stator.

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:

Release the fixing screws of the bottom cup of the RA shaft using Allen wrench and remove the cap rotating it counterclockwise.

Step 2:

Next step is attaching encoder shaft into the hollow shaft of RA axis. Do not touch the cylindrical surface of the encoder shaft with any metal tool (e.g. pliers)!!! You can screw it onto the bottom of the RA shaft by hand and tighten it well enough, as much as you can. This part cannot have any offset compared to the RA axis. If the shaft-threads and/or the connecting front-faces of the parts are clean enough, the thread profile-angle will have to be able to centralize geometrical axes without any problem.

As soon as you have tighten the hollow shaft, please fix it with three fixing screws (worm screws) using an Allen wrench as per below.

Step 3:

Now, place the stator plate onto the house of the RA shaft.

Adjust the position of the plate where the inner hole created for the hollow shaft is concentric with the shaft and there is some gap between them.

Push the stator onto the RA-housing completely and fix its position with four fixing screw on two sides using four pre-installed worm-screws. It is very important to fix this part well against rotation using these screws because the stator cannot rotate at all. Do not apply any plastic or other elastic washers between RA housing and the small fixing plates on side.

Step 4:

Before you could mount the encoder to its place, you need to remove the four encoder fixing screws.

Now, please check and release the three expander screws on the back side of the encoder if necessary and push the encoder firmly onto the previously installed and clean hollow shaft. Please do NOT apply hammer on encoder!!! You just need to push it gently on by hand.

Step 5:

At first, using Allen wrench, please fix both bows (left and right) with four screws removed in the previous step on both sides of the encoder.

Finally, tighten the three expander screws at the bottom of the encoder around the hollow shaft to provide friction-free rotation of the encoder rotor.

Congratulation, you successfully installed the TDM 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 and please check the polar position of your mount before using TDM in the first case.

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.