The basic components for the stepper motor and the drive to the Pentax lens pretty much remain the same. Since I’m using a 1.5 foot ethernet cable to connect the stepper motor to the box containing the Metro 328, I used a small RJ45 breakout board that I attached to the stepper with some 3m automotive double-sided foam tape. And since the iOptron mount, the Metro 328, the stepper motor shield, and the TEC on the astro camera all needed DC power I decided to use part of the project box for power distribution. The Metro 328 and motor shield are powered from inside the box, the 4 power jacks can be used to drive external 12 volt devices, two are presently used by the iOptron mount and the camera’s TEC. The green digital meter is battery voltage and the red is the amps the battery is supplying.
If you decide to make something similar there is something to be aware of. I am using no limit sensors for the focusing, meaning that the stepper motor can drive the focusing mechanism against its internal stops. With the motor I used and my lens that is not a problem but I could see it might be if a high torque or geared stepper motor was used. Also it would be a good idea to use an inline fuse in the battery cable, something that I am planning to do.
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