Justin also provided the H frame as well as a new boom for the 70cm 12 element LFA I had so it could be rear mounted in the centre of the frame.
While I was buying the antennas I also bought a SPID RAS rotator with Rot2Prog controller but more about that in a later post.
The new array took around five days to put but mainly down to the fact I hadn't ever installed this type of system and so it took a lot longer than it would if I was to get it all done again. The main time consumer is in the fact I don't have a tilt over mast and so everything has to put up with the aid of an Aluminium tower.
The array tuned up quite well with each beam within a half a dB of RL.
Top Left Z 50.6, X 3.7, SWR 1.07, RL 28.6
Top Right Z 52.6, X 3.2, SWR 1.08, RL 28.1
Bottom Left Z 53.0, X 2.8, SWR 1.08, RL 28.1Bottom Right Z 51.9, X 3.6, SWR 1.08, RL 28.2
The whole array including coupler and 16m of Ultraflex 10 gave an SWR of 1.1:1
Justin kindly send me a theoretical plot of the array at 8m high with a spacing of 2.2m horizontal and 2m vertical separation.
|Theoretical Azimuth Plot.|
I measured the gain as being 18.48dBi with a F/B of 22dB and a beamwidth of 24 degrees so in good agreement with Justins theoretical calculations.
|Azimuth plot as actually seen.|