Rebuild of the Lower Tower
Updated 11/22/2005

11/3/05 - Today I replaced the lower tower.  It was a beautiful warm fall day with no wind.  So at lunch time I decided to leave work and put up the shorter of two planned towers at the QTH.

I had planned on using 3 midsections of tower that fell at my office, but I found one of them was bent.  So using 2 sections of Rohn 25 from my office tower, one section of one the of towers that fell at home and a new tapered top section I already had, I was able to rebuild the lower tower to 40'.  The original lower tower was 50', but I decided I would make this one only 40'.  I'll put my "rebuilt" A3S up about 5 feet on an aluminum mast.  So the antenna will be at 45'.  I think that will be fine for the 2nd radio and for 10/15 meters.  Despite using sections of towers that fell, the bolt holes were not enlarged, everything lined up perfectly and the tower is straight!

I wanted to mount the rotor but the rotor plate U-bolts were too rusted to reuse and I couldn't find a set in my junk box that would fit, so I'll install it later.  I finished the project at sunset.  It was a beautiful sight!  (How do you like my FEMA roof?)

11/5/05 - Today was a warm Saturday.  I decided to build an A3S yagi out of pieces/parts from 2 of the A3S antennas that fell at my QTH and one that fell at my office during Hurricane Katrina.

Of the three destroyed antennas, only one of the booms was salvageable yet it was bent quite a bit.  I knew it had to be reworked to get it straightened.

Bent boom that needed repair

In order to repair the boom which uses 1 1/2" aluminum tubing, I had to use one of the 12" pieces of 1 5/8" tubing used to join the two sections of boom from one of the two other damaged antennas.  Since the other two booms were damaged right at this junction, it was difficult to remove the 1 1/2" tubing from the 1 5/8" joiner piece.

Once I had a good piece of 1 5/8" tubing, I cut a piece of boom section and made the repair.

Repaired section of the boom

The boom was now straight and I felt comfortable it would hold the weight of the reflector element.

Repaired boom is now straight

The next thing I had to do was to find two element-to-boom pieces that were straight.  Of the six element-to-boom pieces, only two were re-usable and both were slightly bent but not too bad.  I decided not to try to straighten these in fear of breaking them.  Of the three driven element-to-boom pieces, only one was reusable.  It was also slightly bent but did not want to risk breaking the fiberglass insulator.  I then mounted the element-to-boom pieces onto the boom.

The next step was suppose to be a piece of cake.  When I took apart the antenna that fell at my office, I labeled each piece for the director, driven and reflector elements.  And I marked where each section of the elements came together for each reassembly.  But apparently I must have had a brain fart when I built the A3S at the office a few years ago, because the driven and reflector elements did not measure correctly when they were reassembled.  So I was confused until I broke down each piece and compared them to the parts list in the instruction manual.  Once I got that figured out, I was able to complete the antenna but not before finding straight replacements for the end pieces.  Thankfully, I found several reusable end pieces.

Bent element end pieces - luckily I found others that survived the fall

I rebuilt the antenna on a small aluminum pipe sticking out of an old wooden spool.  I was able to reuse one of my old coaxial baluns and that saved time.  By mid-afternoon, the antenna was ready for testing.  With the antenna pointed south and away from any obstructions, I connected it to my radio and found the SWR flat in the RTTY section of the 10, 15 and 20 meters bands.  This was planned as I rebuilt the antenna using 14.1, 21.1 and 28.1 as center frequencies.  As I tuned across 20 meters, I came across a station in Chile with a strong signal.  This was a good sign.

Since there was still an hour or so to go before sunset, I decided to go ahead and haul the antenna up the tower.  Because I used a tapered top section on the tower, I decided to affix the antenna to the top section until I verified my two Yaesu G-800 rotors survived the fall so I could reuse one of them for this antenna.

In the past, I've climbed the tower with an A3S on my shoulder since it's only 26 lb.  But today I decided to hoist it with a rope using the gin pole since the gin pole was already on the tower.  I made a bridle on the boom and walked the antenna up to the house. I then got on the roof and pulled it up by hand and rested it on the roof of the house and attached the line from the gin pole.  I then pulled it up and it went up easily.  I climbed the tower and stabbed it to the tapered top section.  When I finished, it was nearly dark and only a silhouette of the antenna could be seen by the time I was able to take this picture.

Now I had to check out the rotors.  On the work table in my shack, I connected the first G-800 to a controller.  When it started turning, I could tell this rotor was ready for retirement.  The grinding noise was quite loud.  This was probably the older of the two G-800's and it had given me probably 8-9 trouble-free years.  I then connected the second G-800 and it sounded so much better.  I was relieved I had at least one good working G-800 rotor.  By this time it was late and I retired for the night.  Tomorrow I would try to complete the project.

11/6/05 - I got up around 6 a.m. this Sunday morning anticipating completing the rebuild project on the lower tower.  With the antenna already on the tower, all I had to do was install the rotor plate, rotor and mast then slide the antenna up off the tapered top section onto the mast - piece of cake.  But when my wife, Sharon, said she wanted to "do something today", I knew my time would be limited.  So I got straight to work.  It was another warm sunny morning.

I had already removed one of the two rotor plates from the fallen towers and had bought new U-bolts to replace the old rusted ones which had to be cut to free the plate.  But although the new U-bolts fit the hole pattern of the rotor plate, they were too small to go around the leg of the tower.  This was not good news since the completion of the project depended on these U-bolts.  To save time I decided to use the rusted U-bolts on the rotor plate still connected to one of the fallen towers.  Using a drill with a wire brush wheel I cleaned as much of the rust off the threads as I could, then lubricated them with Master Mechanic lubricant/cleaner and carefully worked the nuts off the threads.  Once all three U-bolts were removed, I cleaned them again with the wire brush wheel.

Once on the tower the rotor plate and rotor were easily installed.  I next raised and installed an 8' galvanized 1.5" mast.  Loosening the U-bolts holding the A3S to the tapered top section of tower, I was able to easily slide and lift the antenna onto the mast without ever having to completely disconnect it.  With the antenna resting against the top of the section, I had to climb up to the very last rung on the tower and fasten my belt to the mast.  I never like doing this but sometimes it just has to be done.  I slid the antenna up the mast, rested it on my shoulder and tightened it only so it wouldn't slide.

Since the rotor was left in the due North position, I had to position the antenna due North.  I could not find my compass that morning, so I had to guess at due North.  Looking North, I spotted the Crescent City Connection, which is the main bridge connecting the east and west banks of the Mississippi in New Orleans.  The interesting fact about this bridge is that it runs due east-west, but in the opposite way one might think.  When crossing from the west bank to the east bank, you travel due west and vice versa.  In any case, with the bridge about 8 miles away, it appeared that the entire span was perfectly parallel to my QTH.  So I pointed the antenna directly at the center of the span.  (Later that afternoon I would find my compass and guess what?  The antenna was pointing exactly due North!)

The resurrection of the lower tower and "Katrina" yagi was complete.  Next weekend I'll work on the higher tower.

40' tower with the rebuilt "Katrina" yagi.