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Antennas: Full elevation H-Frame
The four M2^ 18 element yagis being test fitted to the H-frame. They will be nested with in the 4 KLM 18 ele. Yagis for 2 meters. Not the best setup to nest them but all I can do at this time with the limited space and tower locations. The longer cross booms in the image will hold the 15 foot vertical masts for mounting the 2 meter KLMs.
These are two of the KLMs being used for TROPO work now. They will be replaces on the 50 foot tower by a single M2^ 17 ele 5 wave length when the array is ready for the EME tower. The elevation setup consists of 2 each 1/4"X 12"X14" aluminum plates with very large 8" hinges bolted with stainless steel 5/8" bolts. The plates rests together when at zero degrees. The new 18" C-band satellite actuator connects to the front plate that the cross booms mount to from the back and pushes the plate forward. This causes the array to raise in elevation allowing a full zero to 90 degrees.
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thumb nails for larger images. Sept 09,2004 Finally pulled 20 feet of the side tower down and remounted the top thrust bearing plate. Slide the 8 foot 2" OD chrome-moly pipe down the tower center of the tower and raised the H-frame to it's resting point on top of the tower. It had to go up in sections as the complete array is to heavy for the gin pole. So we mounted the frame itself, Then mounted the 4 X 432-18's on their perches in the center of the H-frame.
This places the top of the outer vertical supports for the KLM-18s way out of reach. The top of the tower is just over 20 feet, putting the top of the H-frame at 28 feet, or 18 feet above the roof with the mast still down all the way.. The only way to mount them is to elevate the H-frame to the 180 degs position, and mount the antennas, then bring it back to zero and then be able to mount the bottom antennas. This isn't an easy task being on the edge of the roof. So at night fall here is were we stopped.
The top two KLM's are mounted and the H-frame has been rotated back to the correct orientation. We had to flip the H-frame 180 degrees to mount the top yagi's. With the weight of just the top beams and no beams on the bottom it's very top heavy. Making it very HARD to bring back to zero degrees. So, with no help I had to stop at this point. The frame is locked with an angle bar at around 70 degrees elevation. Friday I'll get some help to bring it back to zero and attached the bottom two beans to add some counter weight to the setup, then attach the elevation jack screw setup back on the frame and get ready for some EME after a few more things like run the hard line, mount the rotor and video cam. You can see the VHF/UHF tower in the back ground were the two KLM's were taken down and replaced with the new yagi setup. More to come. SEPT 10 , 2002 All four of the KLM's are mounted and the H-frame is locked at zero degrees at the moment. Running into a bit of ground clearance issue that I hope to work out this weekend. Still need to run the feed lines and setup the Elevation controls, plus mount the rotor in the tower. Plus do a little adjusting on the array itself. they are all not pointing in the same directions *grin* a couple are 3-4 degrees out of wack. Will fix soon.
VHF/UHF
Amps:
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POR-15
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