Thursday, September 17, 2015

New Beam Antenna Build at N6QW ~ Part 16

Final Assembly of the Mosley MP-32-N

Additional photos added on 9/17/2015
Today I spent working on two activities. The first is the final assembly of the beam itself and the second to raise the mast to the final height so I could cut to length the guys that will be used. The SpiderBeam mast uses two sets of guys wires and thus we will have six lengths of wires that we must fit and cut. Below are photos of the beam as it is assembled into the final configuration. The instructions were silent about some aids that would make the final assembly of the beam an easier task than simply putting Tab A into slot B.
My approach was to build each of the two halves of the driven element and reflector and THEN assemble those on the boom. I used some wood blocks on my picnic table to keep things  steady and level so that the two elements ultimately end up in the same horizontal plane when installed on the boom. The several photos with the coax connector is a mod from N6QW and somewhat put down by Mosley. In essence Mosley said unless you can keep the leads less than 2.5 inches don't do it. Well I am at 3 inches and so I am going for it. Mosley claimed the loses would be too high by using a coax connector. The cable I bought has super premium PL-259's installed (costly) and so I think I will be OK with the extra 1/2 inch lead length --we are not operating at Microwave frequencies here.
Pete N6QW

The next several photos show how I tested if the boom to mast bracket was perpendicular to the boom. I first made certain that the beam elements were in the same plane and then I installed a short section of mast that I had in the junk box. I then firmly affixed the boom bracket to the masts section and then moved the portion that attaches to the boom small increments so that a level placed on the mast section was "plumb" in two direction. Next I carefully tightened the U bolts which affix the adapter to the boom and we are there. Bob's your Uncle. We are really getting closer to B Day.
Pete N6QW

The second task was to "psych out" what was needed for the buying of the mast. The Radio Gods smiled down on me! It seems like I can use the wooden fence on three sides of my house as the guy anchor points for the mast. Luck Indeed! This test was just for the top most guys. I ran out of ti9me and will install the 2nd set tomorrow. Same anchor points.