Month: March 2018

After almost three weeks of rain, snow, freezing temperatures, more rain, and more snow, a couple of days ago spring broke through. The ground has dried out, the snow on the local mountains has disappeared, and everything was ready to move to the next step with the antenna mast I’m putting up in the back yard.

I ran across a “handyman” by the name of Jimmy who was willing to come over and help me get the foundation dug and the cement poured. Yesterday I picked up 21 eighty-pound bags of Sakrete from Home Depot. reserved a cement mixer for today, and got all the tools in readiness. Jimmy arrived a little past noon and we got underway.

When the hole was the right depth we built the cement forms to provide for two feet of concrete with the 4×4 posts in the center. Then we fired up the cement mixer and proceeded to mix twenty-one bags of concrete and pour that into the box.

Three hours later, 2,500 pounds of concrete were in the box ready to cure. I’m pretty sure the wind won’t blow this over!

Jimmy will come back on Monday when we’ll take the forms apart and fill up the hole.

Between the two posts is where the 3/4″ galvanized steel pipes will sit. Bolts through the posts and the pipe will secure the mast to the posts. The top bolt, which will be about six inches below the top will serve as a pivot point. Two more bolts will secure the pipe.

The concrete comes up to about three inches below ground level so it can be covered with dirt and grass planted around.

One last item to stick in before we fill in the hole is a copper grounding rod. The galvanized pipe will be secured with a copper strap to the grounding rod. We don’t get much lightning around here, but it’s still a very good practice to ground the pipe!

So, Monday the hole will get filled in and I can start on the mast. I won’t need Jimmy’s help with that.

As described in an earlier post, the mast will be thirty-five feet high with a pulley afixed (about six inches from the pipe) to haul up (or down) the G5RV antenna. The window line will come straight down and mounted (with a six-inch standoff) to the 4×4 posts. I’m also going to put a two-meter J-pole antenna at the top of the mast and use that for an AllstarLink node I want to put up here in Tooele. So I’ll be running two coax cables out to the mast. One will be LMR-400 which will connect to the G5RV and the other RG-213 that’ll connect to the J-pole. I’ll run a messenger line from the edge of my roof out (about twenty feet off the ground) to the mast with carabiners every foot or so and the coax will ride in the carabiners. The coax then goes down a pipe up on the roof that I had installed when we built the house and into my shack.

When this is finished in the next couple of weeks, I’ll have the full-sized G5RV running roughly north-north-west to south-south-east diagonally across the back yard. The 2-meter J-pole will be atop the center mast holding up the G5RV.

Across the peak of the roof is a G5RVjr which barely fits on the roof. To the side of the house up about 20 feet are some military poles on which a 2-meter/70cm J-pole is mounted along with a twenty-meter ham-stick dipole. That antenna is oriented north and south to fill in the gap from the G5RVjr across the roof of the house, running east and west.

That will be 5 antennas. Enough for now. I’ll have coverage on 80-meters through 70cm across these antennas. Should be enough for a while.

 

When I first designed the mast to hold up the ham radio antenna, I felt that three feet below the ground encased in concrete would be sufficient. The engineer, however, came back and said the hole should be four feet deep with 24″ of concrete around the 4×4’s four feet deep (or just about one yard of concrete).

Several weeks ago the contractor who built my house had a track hoe working on a house down the street and he obligingly (and at no cost!!) dug me a three foot by three foot by three foot hole. I was amazed at the number and size of rocks that came up out of that hole. We have very rocky soil here in Tooele, thanks to ancient Lake Bonneville.

This morning I started digging and prying to get another foot or so down. After two hours, I think I’ve gotten four or five inches down. And this 73.9534 year old man is wiped out (another birthday Real Soon Now).

So, I called a handyman listed in the newspaper classifieds (remember those?). He can’t come over until Saturday, but thought he might be able to find someone who could come over on Wednesday. I think I’ll have him help with the whole project including mixing and pouring the concrete and backfilling the hole. Supervisor sounds much better than worker at this point!

The engineering firm completed their work last Thursday. The changes they asked for were minor. They felt that a 24″ diameter footing four feet deep would be better than a three-foot deep foundation. That means 4′ below ground and 4′ above ground, moving the pivot point down one foot.

Everything else was just fine. “The bolts and anchoring posts are sufficient to resist lateral loads at the base.”

So this morning I picked up the starting materials, the 4×4 pressure treated 8′ posts, the first length of galvanized steel conduit, and a bag of Sacreet cement. I’ll get the 4×4’s spaced properly, drill the pivot bolt hole in the 4×4’s near the top, and mix up some concrete. I’ll stand the 4×4’s in a Home Depot Homer’s Bucket and fill that with concrete. That’ll set in the garage for a couple of days before being moved to the hole in the backyard.

The hole is currently three feet deep. I’ll have to climb down there and dig out another foot. I’ll do that while the concrete is setting in the bucket in the garage. That’s going to be a Very Heavy Bucket!!!

I still need to stop by Tooele City Planning and get their final approval. I talked with the guy on the phone and read him what the engineer said. He grunted, then said I could proceed but to stop by his office to drop off a copy of the engineering. I’ll do that on Monday.

It’s going to take a week or so, but the mast is coming. I’ve decided to put a 2-meter J-pole antenna at the top of the mast to use for a Allstar node. I’ve got the radio, the Raspberry Pi, and interface unit. It just needed an antenna.

Of course, an antenna needs coax. I had my trusty Xfinity installer guy (lives up the street) come over and climb up on the roof. I have a hundred feet of LMR-400 coax, so he fed that down to me along with a length of Radio Shack RG-58U coax (very lossy coax, but should be sufficient for what I need for an Allstar simplex node). The LMR-400 will connect to the G5RV antenna and the RG-58U will connect to the home-made 2-meter J-pole.

More as the project nears completion.