At ED1R we use industrial ball bearings on our towers to turn the antennas. The ball bearings are reliable IF you protect them properly. We learned this lesson the hard way. After almost three years in service, I feel confident sharing our solution for adequately protecting the SKF bearings on antenna towers.
At our Contest Station ED1R we are limited in space. Therefore we have to install before the contests our low band verticals and beverages - and of course, after the contests, take them down and bring them into the storage again. Over the last years, we started optimizing the way how to rapidly deploy and remove radials. Earlier we used a bunch of garden hose carts, which were inexpensive, but after three contest seasons, they started falling apart. A more solid solution was needed. This time we build a solid cart, using surplus military equipment.
Once your contest station grows bigger and you add more antennas to turn, it becomes quite annoying to move around the physical rotator controllers between the operating positions inside the shack. Desperate for a better solution, I developed a server software that provides access to the Rotators through the network. Now all rotators can be controlled either directly through Win-Test, TCP socket, or through a Web-Interface.
I was curious if the performance of our 4O3A high-power Bandpass filters could be improved with additional coax stubs in parallel. We were operating at ED1R for some time now with the added stubs, and we are pleased with the results. Check out the details!
At our contest station ED1R we have no space for permanent Lowband Verticals. Each Contest, the verticals have to be installed temporarily in a field nearly. Especially the deployment and removal of the antenna radials are very time-consuming. Over time we optimized our system which reduced the required time from 2 hours down to 30 minutes.
Until today, I’m fascinated by what can be achieved with good filters. At our Contest Station ED1R we bought a Triplexor (10m/15m/20m) to be able to use our new Optibeam OB11-3 on the three bands simultaneously.
Over the last few years, I spent a lot of time simulating antennas. One annoyance I encountered over and over was the unavailability of values for ground conductivity and the relative permittivity. Two figures have quite an impact on the antenna performance, especially on vertical antennas. This finally led to the conclusion that both figures need to be measured. In early 2012 I built a measurement kit and finally determined ground conductivity and relative permittivity at our contest station.