Finally I made it: my first ever qso in CW via satellite (RS-44). As I only have a free open view of less than 90 deg from my balcony, I have to wait for the right passes, and the time window is usually maximum 10 min.
Setup on the balcony
Using the IC-9700 with the 5 element log. per. antenna on my home brew az/el rotator, I was able to hear my own CW signal from the satellite and manage a qso with E21EJC in Thailand!
Software is Gpredict with Hamlib running on my Mac.
For my VHF/UHF station I am using a dual band five element log-per antenna, similar to the Elk log-per. It is actually an ideal antenna for portable use, as it can be assembled and disassembled easily and packed in a small size. Now the idea came up to use it for satellite communication with my FT-818. The only thing missing was a azimuth/elevation rotator to track the satellites.
I started with my own design, using a stepper motor for azimuth and a servo for elevation. After a while I cancelled the project, as I had too many problems with electromagnetic interference to the servo.
I decided to build it, but to separate motors and electronics; purchased the parts and started the 3D print design. Below the details and the final result.
Overview of all 3D printed parts
Tripod mount
Top mount with hub for azimuth motor
Motor unit mounted to a 32 mm PVC pipe
Housing for electronics, inside view
Housing attached to the pvc pipe
Cutout in the housing
Rail to attach the housing to the pipe
Counterweight using two ferrite torroids
Sensor housing
Antenna holder
The whole package ready for portable use
Test on my balcony
When I first time applied power to the motor drivers, the following happened with a loud bang! Luckily, it was outdoor on my balcony.
The 100 uF capacitor was faulty, this is the result after applying 12 V to the board.
My thanks to SARCNET, the software works w/o problems. I only had another EMI problem, which could be solved finding a well screened micro USB cable and adding a few ferrites.