How it happened we still do not know but in the middle of the 2022 CQWW contests our main tower with the 20m and 10m yagi’s on it gave problems again. For the 2nd time in 8 months the new Optibeam 20M5 had a mechanical failure at the feeding system and the ProSistel rotator in the tower started to show very strange direction readings on the controller.
The only remedy left was to take the tower down and do some repair work on both the antenna and the rotator hoping that the rotator could stay in the tower to solve the issue.
Friday, January 24, it was all hands on deck so that at worst we had 3 days available to do the necessary work.
The work on the antenna was done quickly with the available aerial platform and after a few hours the antenna was ready for use again.
However, the work on the rotator was considerably more complex after some measurements inside the mast because everything pointed to the potentiometer inside the rotor being defective and needing to be replaced. A good quality replacement was already available but this meant that the antennas had to be detached from the rotor, take the rotor out of the mast, open it up and replace the potentiometer, test it, put the rotor back in the mast, calibrate it with the antennas on it and reassemble everything.
Given the darkness and cold, the rotor was not put back on Friday but on Saturday morning so that finally Saturday afternoon the whole job was completed.
Many thanks to chief mechanic Kees PA3BWD and his assistant at altitude Ton PA1CC, but also to the ground crew consisting of Ronald PA3EWP, Ronald PD0VIP and Alex PA1AW, for braving the cold and their efforts to get the station ready for the PACC Contest (and the Bouvet 3Y0J DXpedition).
Below is a photo collage to give an idea of the activities.