Tuesday, October 3, 2017

WHEEE! The Antennas are Mounted and Aligned

WHAT A DAY!  My good friend Tim, K8RRT, came by today to give me a hand with mounting and aligning the antennas.  It's pretty certain that without his help, I would not have been able to do this on my own, even with Evelyn helping.  There is only so much I can do by myself at my age and having Tim give me a hand when I need it is priceless!  THANKS, TIM!!!

Yesterday was a day that did not go very well.  I spent a lot of time trying to find a drill bit or some way to drill a 7/8" hole in my PVC box for the LNA and T/R Relay.  The local electrical supplier had a Unibit that would have worked but they wanted $51.60 plus tax for it.  Too rich for me.  Finally I ordered one from Amazon that will be here tomorrow for $9.98 total.  But all the running around yesterday including getting blood drawn led to me forgetting to take my daily medications.  Coupled with a couple of short nights, I was pretty bummed out and "couch bound" for the afternoon/evening.  But, after a good night's sleep and taking my meds, I got up this morning in a much better mood and feeling like I could whip anything.

On Sunday I had gone to Lowe's and purchased a 1-3/8-inch diameter Poplar dowel rod.  I bought this because when I first attached the antennas to the Fiberglas boom, I was uneasy with tightening the bolts too far for fear of cracking the Fiberglas boom.  I bought the dowel to make a plug to fit inside the boom and provide strength for it.  Unfortunately, the dowel was just a tad too big to fit.  Therefore, my first job this morning was to clamp it in the WorkMate and run sandpaper over about a foot of the rod until I sanded off enough wood that it would fit.  It only took about an hour or so and four trips up the stepladder to check the fit.  Once I had the dowel sanded down to size, I cut two 6-inch pieces off the end and sanded them again.  At that point I gave them a light coat of Polyurethane as you can see in the photo on the left.  Throughout the morning, I gave another coat every 1-1/2 hours for a total of 3 coats.

When Tim and I had reached the point where we were about to align and tighten the antennas, Tim inserted the dowel plugs with a light coating of glue to make sure they stayed in place.  When he tightened the antenna-to-boom mounts, he said he felt very comfortable with the plugs in place and was really able to tighten the antennas to the boom.  NOTE:  After looking at the photo on the right, I decided to drill a drain hole in the lowest point of the Fiberglas cross-boom to allow any accumulated water to exit the tube.  This should prevent water build-up and subsequent freezing that could fracture the tube.

Tim and I also installed the rearward facing boom to support the LNA and T/R Relay Box as well as the 2-way power splitter.  We aligned it in the same plane as the antennas and put most of the hardware (LNA, T/R Relay, barrier strip, coaxes, etc.) onto the rearward facing boom to see how well the system was balanced.  Once we had all the materials in place, we engaged the Elevation rotor to pull the front of the antennas off the roof.  Everything held in place and the Elevation rotor was easily able to move the antennas up and down so we decided that the balance was close enough.

There was a good bit of "trial and error" in getting the antennas aligned and Tim was really patient with me (who wants everything PERFECT) and we did it again until the two antennas were "nearly" perfect.  "Good Enough for Government Work" was the standard we settled on - Hi!

Once the antennas and the rearward boom were aligned, we raised the Hazer cage high enough to be able to play with the rotors.  My external Rain Proof Hoist Crane Pendant shown at the right was just exactly what was needed.  Not running into the shack to turn a rotor!  SWEET!  At this point we calibrated the elevation rotor to the array by loosening the clamps on the Elevation rotor and running the rotor until it matched the measured angle of the array.  In practice I will be using an Inclinometer but I wanted to make sure the rotor was not near a "stop" that could cause operation of the rotor to cease at an unexpected point.  Click on any image for a larger view.

When we finished all the above work, Evelyn had prepared a scrumptious lunch of "Meat Lover's" Lasagna, tossed salad, broccoli with cheese, Brussels Sprouts, and Garlic Bread.  Then chocolate iced chocolate cupcakes for dessert.  YUMMMMM!  Just what a couple of tired Antenna Jockeys needed!  THANKS, DEAR!

We then took a 15 second video of the antennas in motion which you can see on YouTube at the link below:

The video shows the antennas moving DOWN and then CCW.  Note that at that point they are moving in both directions (Down & CCW) simultaneously.  If you pause the video just before it ends, you can see a square metal tube (the rearward boom) extending to the rear of the array between the antennas.  Near the end of this is the grey PVC box for the LNA and T/R Relay.  Beyond that is the Power Splitter to which each antenna connects.  The antennas will normally be much higher on the tower.  I just kept them low so that we can adjust the tuning of each of the antennas and so that I can wire the cables into the LNA/Relay box.

This was a BIG-TIME day on the 2-M EME project.  I'm getting so close I can almost taste the moon-rays!

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