Rebuilding the tower and antennas at VE1DX's amateur radio station
The day after VE1DUN and I cleaned up the mess from the tower and antennas destroyed in the windstorm of 1 March 2005, we began the process of re-building. For while a DXer can work with wires and the like, nothing performs better than a Yagi at 50 feet (14.6 metres!) I managed to obtain a replacement tower. Before it could be erected, we needed to make some alterations. With Delhi towers, normally the rotator sits in the top section about 4 feet below the top plate. This is a proven design, having been used for decades. A few years ago several of the local Amateurs felt that it would be stronger and less susceptible to sideways stress if the rotator were lowered into the 2nd section, putting it about 10 feet (3 meters) down from the top plate. In order to do this, the "factory" rotator plate needs to be removed and a larger plate inserted about at the middle of the next section.
2nd Section From the Top, With "new" Rotator Plate
We then assembled the two top sections temporarily. This was necessary to make sure the newly installed rotator plate was level, and that it would line up the rotator with the thrust bearing on the top plate. Both the rotator and thrust bearing are made by Yaesu, and although they are high quality, new holes have to be drilled in the rotator and top plate. All of this, combined with a 20 foot (6.1 metre) mast means that there is significant room for human error. It is far better to put it together temporarily on the ground, and test it there, that it is to find out that something is wrong when you get it in the air. We were lucky the first time as everything lined up perfectly, and we could turn the mast without any jamming.
Then we he disassembled the top sections, mast, rotator and thrust bearing. They is needed later when the tower is up in the air. The next step was to begin adding the larger bottom tower sections to the concrete base. Although the legs in the concrete base were from my original Delhi tower, Michael, VE1DUN, and I spent a considerable amount of time in order to get the new bottom section to fit. This was because, although they were both the same model of tower, no two are made exactly alike. After about an hour, we managed to get everything in place, and we bolted it securely to the base.
Bottom Section Bolted to the Base
The next task was to add the second section. Since there were only Michael and I available that day (and we had been doing tower work for almost two days), we decided to just put the second section on. We were both getting tired and the bottom sections weigh 75-85 pounds (34-38 kg.) I sat in the top of the bottom section and VE1DUN carried the section up, and we both dropped it into place. We secured it to the bottom section with 9 bolts.
VE1DUN Getting Ready to Add the Second Section
This part sounds hard, and it can be if you are not careful, but we managed to get it installed in a fairly short time. Each section is 8 feet (2.44 metres) long, so we ended up with 16 feet. It's still a long way to go to reach the top, but we have a good start.
The first 16 feet of the New Tower
The next day was fine as well, so we decided to continue. This process was getting harder, for although the sections were slightly lighter, they were higher in the air. We were going to try to get two more sections up, but by the time we got the next one on place (making it 24 feet - 7.3 metres), the wind had picked up and we decided to stop for the day. At least the tower was half assembled, and we were going to wait for the next fine day.
24 feet - halfway there
The following day wasn't quite as fine as it had been, but it was still possible to do tower work. Michael and I had decided to let it go for a week or so, but Mike, VE1TK, called me and suggested we try to complete the tower. He came over around 10:00 PM and we started adding sections. By 1:00 PM the entire tower was completed! It was a bit windy, but Mike wanted to press on and install the Comet GP-9 vertical for packet radio. We took a break for lunch, and then Mike climbed the tower and put up the vertical.
Mike, VE1TK at 48 feet (14.6 metres) installing the vertical antenna
After four weeks without a tower, it really looked good to have it back. We still need to assemble the TH5-MK2 HF beam and raise it to the top of the tower. However, that is something that can wait until the weather gets warmer. The tower installation went quickly, but had we gotten cold weather or snow, we could have waited with the tower partially completed. Once I start to put the antenna together, I will need to have at least two consecutive warm sunny days to assemble and lift it up to the top of the tower.
Tower Completed - 2 April 2005
We got our fine weekend on 9-10 April. Michael, VE1DUN, and I decided to put the TH5-MK2 together. The manual that came with it said it was about a 6-hour project. Right! Maybe if you were a mechanical engineer at Hy-gain and had put a hundred of them together before. It took us 15 hours total! By about 4 PM on 10 April we finally had it completed. The next step is to get it up on the tower. We'll need a fine day with little to no wind as this antenna weighs 57 lbs (25.8 kg.)
Hy-Gain TM5-MK2 assembled on the ground
On 16 April 2005, we finally got a fine day to occur on a Saturday. My son Michael, VE1DUN, and Mike, VE1TK, were available to help put the beam up. We started around 8:30 AM. The temperature was around 12-14 C and there was no wind. Wind, rather than temperature, is usually the critical factor when lifting a beam of this size to a height of 50 feet.
We had made up a rope and pulley system to attach to the aluminium mast. VE1TK climbed to the top and clamped it to the mast, 4-5 feet above the top plate on the tower, and then pulled the rope through it. Then Michael and I pulled the antenna to the top while Mike "walked" in up the side of the tower, making sure that it stayed level and didn't get tangled in any of the other wires or tree limbs.
"Home Made" antenna lifting pulley that clamps to the mast
Once we got the antenna on the top plate, Mike VE1TK, did most of the work. Neither Michael, VE1DUN, nor myself, VE1DX, are good at climbing. If absolutely necessary I can climb to the top of the tower, but at 50 feet in the air, I find it very difficult to work. Thankfully VE1TK has always helped me with the tower work, and he is an excellent climber. He always marvels the rest of us amateurs with his ability to work at 50-75 feet. He also has a natural talent for finding common sense solutions to configure coaxial and rotator cable runs, making rotation loops in the proper manner and a dozen other things that ensure that not only is the antenna securely fastened to the tower, but that it works properly from an electrical and RF standpoint.
Mike, VE1TK, working on the cabling
By about 1:30 PM the job was completed. We would have been done an hour or so earlier, but we had to install a 2-metre (144-MHz) yagi beam near the top of the tower. This beam is used primarily for the VE1DX-L EchoLink node. You can see it attached to the black pipe in the pictures below.
Looking up from the bottom of the tower
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Last updated on Thursday, 12 April 2007