DIY: Motorizing a PST40

Since I do 90% of my H-alpha observations with a camera, I was faced with the problem of how to focus and adjust the transmission line. It was very difficult outdoors in the sun using a laptop or tablet, as the manufacturer of the devices with the bitten fruit seems to be totally into reflective displays. While I can see if I'm dressed correctly, I can see very little of the sun image.

So... a solution is needed.

Motorized Focusing of the PST40

For the motorized focusing, I chose a project by Robert Brown: MyfocuserPro, since this is a private conversion. I will develop an adaptation of the ZWO EAF motorized focuser at some point, if I notice sufficient demand. Robert did a very good job; his focuser (there is now an ESP version with many features) is easy to replicate.

A stepper motor is mounted at the appropriate angle and connected to the original focus knob of the PST40 via a toothed belt. This is a non-invasive conversion, as the focus motor, including the circuit board, is attached to the screw on the bottom of the PST40.

Finished assembly. Here, the timing belt for the Etelaon is still 3D printed, but it will be replaced with a regular one.

The two stepper motors are controlled via INDI via AstroBerry.

The 3D files in .stl format are available upon request; I'll be happy to provide them free of charge.

Please find the pictures in the german version!