Portable EME test on 10 GHz 12/8/2018 using 1.2 metre prime focus dish. The tracking system was previously used with a 900 mm offset dish (2017 EME Portable work). The same transverter that has been used since 2016, 30 watts with approx 0.7 db NF. The WR-75 dish feed is a Miteq chaparral feed as used by Rex VK7MO. The complete system will run for a few hours on battery however we had 230 VAC mains back up this time around.
The tracking electronics uses a modified VK5DJ controller (vk5dj.com) with a GPS and time clock. The AZ and EL sensors are HH12 from Georg DF1SR that use Austria Microsystems AS5045 12 bit absolute encoders readout to 0.1 degrees. H bridge motor drivers and an Ublox NEO8N GPS.
ON boot up the tracker waits for the GPS to lock then updates the Lat, Longitude and time in the controller for the location. All that is required then is to calibrate the system by DF'ing either the Sun or Moon on noise and hit "CAL". The moon is then tracked for the complete pass.
Location for the test was at Keith VK5AKM's QTH (PF95im) about 60 km's North of Adelaide in South Australia. It is winter in Souther Australia and intermittent heavy rain on the day prevented operation for the complete EU window. OZ1LPR worked on QRA64D, COFM on 10368.210 MHz signals -11 db , my report - 22db.
11 авг 2018
