This was an experimental mount that I built to test a theory. It DOES work as I planned, and I'm putting it up here so that others may be inspired to try their own version. To be honest I don't know if the idea is original to me or if I got the idea from elsewhere.

I wanted a way to track a satellite with a small scope with a mount that moved in only one axis, no matter where the satellite's path appeared in the sky. I came up with a theory. What if I used the polar axis portion of a German equatorial telescope mount, aligned the polar axis with the north pole, and mounted a scope that was aimed at 90 degrees from the polar axis,what would happen? The scope would track the stars at zero latitude (over the equator) perfectly. I used the declination shaft portion of the German equatorial mount to hold a scope. I left out the center portion of the mount.

Next I got a program that gives a satellite's closest approach. The I set my mount so the "polar" axis was set at a spot in the sky that was 90 degrees from that spot. Then the scope would be pointed at the location of the closest approach. The mount then allows the scope to follow the satellite as it travels across the sky.

The mount uses a floor jack. The upper end rotates in the lower end. I installed a degree wheel that gave me the azimuth The degree wheel is attached to the lower part, a pointer to the upper portion. I made a degree wheel by gluing two protactors to a piece of plywood and renumbering the degrees on one side so it would read from 0 to 360.

 Then it was simply a matter of pointing the scope at the north star, set the degree wheel to indicate 0 or 360 degrees azimuth and used a protractor to set the altitude at 40 degrees - my lattitude. Of course, to be precise these two adjustments must be done 6 hours apart - the azimuth when Polaris is north or south of  the north pole, that altitude when Polaris is directly east or west of the north pole. I later discovered an easier way to set things up - point the scope at a planet and use it's azimuth and altitude to adjust the degree wheel and check the altitude. I had to be sure the scope was pointed directly "ahead" so I pointed the scope directly up and used the protractor to make sure it was pointed at 90 degrees and then marked the mount so I could reproduce that alignment every time.


Here is my original mount.


Here is my present setup. I set the protractor on top of the scope to set altitude.



Here is a closeup of the degree wheel.


Since I wrote the above I discovered that the idea wasn't new to me. There was something called the Baker-Nunn camera that used the same concept to track Earth orbiting satellite. Here and here are links to pages that explain them:

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dishhead@insightbb.com