The Intelliscope System - Malte's Scope
by Malte Uhl

Editors Note
Edited by Mark De Smet

I had created the Intelliscope Page so that others could learn more about the intelliscope system, how to modify it, and even possibly use the intelliscope system on a non-intelliscope.   In the approximatly 9 months since putting that page up, I recieved a number of emails from people who were interested in learning more about the system, and installing it on another scope.   Malte Uhl decided to give this a try on his Dobsonian and emailed me to let me know the results.   Below is what Malte wrote and pictures he took.   If you would like to email about the hosting of this page, or the Intelliscope page, you can email me, Mark De Smet).   If you would like to contact Malte, you can Mail Malte).


I first came across the Intelliscope series at last years ITT, which is maybe Europe's biggest Telescope meeting, held annually in Austria, in the Alps.   While I was not impressed with the optical performance of the 12" on display, I immediately found the DSC system very helpful and well designed in terms of ergonomics.   After a bit of a discussion, the dealer promised to sell to me the Object Locator and two altitude encoders for 250 (1 ~ 1.3$).   Of course, he was unable to get hold of another encoder, but finally, I got what I ordered.   I suspect that he simply took the encoder from another controller kit.

So finally, I had the computer, two encoders and the wires, but not the connector board.   I didn't want it anyway, because it requires a hole in the rocker box for the socket for the computer.   I fixed a small circuit board for that.

Thre problems had to be overcome to make the Object locator usable with my Dobson: Problem 1 was solved by getting a specially made bearing, that consists of a mounting plate and a coaxial cylinder, essentially the same thing as the bushing depicted on your web page, but screwed to the lower half of my rocker box.

Problem 2 remains to be solved.   Currently, the altitude encoder is simply screwed to bearing.   Their diameter is smaller than the circuit board of the encoder, so I simply use a long screw through in the rocker box to keep the board from moving in altitude with the encoder disc.   I'm thinking about clamping the circuit board to the rocker box so that it can be attached and detached without tools.

Problem 3) Wiring turned out to be unexpectedly tricky.   The spiral cord connecting the object locator is made from wires that simply cannot be soldered reliably to anything.   The conductors are very thin and break easily.   So I got another RJ-11 connector with non-spiral wires.   Anyway, the wiring diagram you've given is correct.   I used an experimental circuit board instead of the connector board since I had not decided on which way to mount the encoders.   I believe that it is possible to reverse the encoders directions by simply "swapping" the hall encoders by crossing their connections.

After everything was mounted and connected, the system worked perfectly at first try.   I was particularly impressed by the pointing accuracy.   Using Vega and Capella as alignment stars, precision was good enough to have all targets visible in my lowest power eyepiece, which gives about 1.5 field of view.   The warp factor is always in the range of 0.3-0.8.


Rockerbox bottom
The above picture shows the rockerbox from below with the upper and lower half detached.

Original bolt and bushing
This picture shows the bolt and bushing that originally connected the two peaces.   Essentially, it's only keeping them from falling apart, allowing lots of lateral play, which makes it unusable for precise angular measurements.
Replacement bushing
It had to be replaced with the purpose built part depicted in above.   The base plate gets firmly attached to the bottom part, leaving only minimal play to still allow the upper part to rotate easily.   This is shown in the next 5 photos.
Azimuth axis 1 Azimuth axis 2
Azimuth axis 3 Azimuth axis 4
Azimuth axis 5

This shows the two altitude encoders.   The second one was cut to 15mm length, to avoid interference with the moving telescope.   I really didn't want to change the altitude bearings of my rocker box.   The next two pictures show how I attached the encoder to the bolt in the center bearing.   No, the circuit board is not bent.
Mounted azimuth encoder Mounted azimuth encoder

Original Alt bearing
This shows what the altitude bearing looked like originally.   The telescope once was a GSO880.   It has the typical spring load mechanism used by this manufacturer.

New Alt bearing 1 New Alt bearing 1
New Alt bearing 1
These three show that I simply removed the black plastic bushing from the altitude bearing instead putting the altitude encoder in place.   By lucky coincidence, it fits perfectly!
All connected
In the above picture you can see all the bits and pieces connected experimentally.   And the last picture shows the posessions of one happy Orion customer in action.
All connected
So, I hope you like it and that my pictures may be helpful to others.   Things remaining to be done obviously are

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