The tower season started early in 2007. January saw 2 big ice storms that damaged both of the 40m4LLDD antennas. In the first storm the top one had one of the element trusses break:
Fortunately this was followed by an unusually nice stretch of weather so we were able to quickly get together a crew and take it off the tower before it was damaged any more. The crew assembled on a nice sunny January morning.
I had already rigged up the ropes and tram wire, but was hoping to be able to do a temporary repair without removing the antenna from the tower.
With everything disconnected from the tower and the wind starting to pick up I decided to abandon the repair option and just get it off the tower.
So down it came:
The damaged part:
What it should look like:
What I didn't get pictures of...
The next ice storm a week or so later broke 2 element trusses on the lower beam that was still up on the tower. The weather had turned back to a normal Peru winter so I called KC1XX to come remove that one, which he did on a day where the high temperature might have been +10f with 20-30 mph winds. Ironically the one on the ground broke a second truss in the same storm while sitting 5' off the ground on my construction tripods.
I adopted the N1IW modification route which consisted of drilling out the center clamp hole to 1/4" and adding a stainless steel shackle, eye, and 2 cable clamps to make a proper clamp for the phillystran cable. When removing the old cable for the modification ALL 12 pieces that hadn't broken had cuts in the jackets on the first inside bend. When talking with the M2 people at the Dayton Hamvention they said they had a new strain relief mechanism but didn't have one there to take a look at.
The modification looks like:
The lower antenna was modified in the snow and put back up the tower at the 70' level for the ARRL DX contest. I was originally going to put it back at 105' where it had been, but it got caught up in the guy wires on the way up so it ended up just above the 70' guy wires where I was thinking of moving it anyway to make it rotatable on a ring rotor. The TIC ring was installed later in the spring. The upper one didn't get raised back up until Friday before WXP CW... when we again had enough ground crew to take a few pictures.
The the picture below shows the rigging for the tram pully. The tram wire in this case was just barely long enough to reach the guy anchor for the tower where the antenna was sitting on the tripods. So the pulley in the picture below is on the tram wire just above the dead end, the cable to the right is 1/4" aircraft cable going to the come-alongs. I connect to the boom with the heavy rope in an upside down V arrangement so there is room to sit the boom in the ring rotor cradle without removing the rope. I also think this helps spread the load on the boom a bit and makes balancing easier. The rope down to the right from the pulley is a safety line holding the beam down in the tripods until we are ready to have it take off.
Liftoff in this arrangement is done by tightening the come-alongs. This pulls the tram wire tight and lifts the antenna up to about 20' above the anchor point before we start to pull it up the wire with the jeep. All hands were busy for this part so sorry, no pictures. Once it is off the ground and moving up the wire its just a matter of keeping it pointed at the tower. As you can see below, this was a perfect May morning for this job, not a cloud in the sky and very light winds. You can see the two tag lines and the white lifting rope below, but the tram wire is hard to see.
As the antenna goes up the force on the tram wire increases. We had to stop two or three times to take a few more pulls on the come-along to raise the antenna above the guy wire that it was over. The only problem this time was that the rigging I had planned to tip the antenna a bit to get the elements above the top guy wire didn't work well enough so I had to go up and give them a bit of help.
Once sitting in the cradle of the rotor it just takes a short time to hook up the boom brace, the 8 bolts for the boom clamps, and level it out. The star guy bracket makes a nice chair to sit in while connecting things up:
Then all the tram wires and ropes have to be lowered and put away... The ground crew cleaning up:
KB1W gathering up one of the 3 come-alongs (2 in series on the tram wire because one wasn't long enough, and 1 on a backstay).
KJ1K and a neighbor in the shed watching the final connection. K1MK was behind the camera.
Time for a contest!
On to Part-2 ...