Mast take-down and 7m dish maintenance

Sunday, April 10, 2011 we met at OZ7SAT to start working on our antennas. The weather is becoming better and we have a few plans for upgrading the antenna farm at AMSAT OZ headquarters.

First task was to take down a mast that is no longer used. It was equipped with a single Azimuth rotator for terrestrial use. Since it has been unused for quite some time, we decided to take the mast down and use the support platform for a brand new 2.5 meter dish with an Alpha Spid Az/El rotator for space communications. We are not yet sure what to use this antenna for, but generally it will be good for uses where the 7 meter dish is just too big (in terms of pointing accuracy vs. beam width on microwares). We are also thinking about trying to receive HRPT imagery on 1.7 GHz from the NOAA polar orbiting satellites. That would be an interesting challenge.

I also recorded a timelapse video of the actual take down:

Our 7 meter dish may also require some maintenance. There is a leak on the hydraulic drive system but it is not yet decided whether this leak is big enough to justify the expensive repair. According to experts there is always some leak in a hydraulic system. For now we just took a look and will keep an eye on how much it leaks. I also got a quick crash course in operating the lift that goes up to the dish 🙂

Author: Alexandru Csete

Embedded software engineer in the satcom industry during the day. Radio amateur and SDR hacker during the night.