WB2FKO Tower Project:   The Hazer Nightmare

                        

 
A high SWR in the antenna system took me off the air on April 11, 2004. That meant the array had to come down for inspection and some troubleshooting. This, of course, is exactly the reason I purchased the Hazer tram system in the first place. The simple lowering operation, however, turned into an enormous problem. Halfway down the tower, the Hazer got stuck. I determined much later that the hangup was caused by a section of tower not being quite straight. And it was ultimately the optional caster wheels -- the wheels that are supposed to make the raising and lowering operation so smooth -- that stopped the downward movement. The steel guy wires are attached directly to the Hazer, so I pulled on these to try to get it moving with no success. Then I attempted to crank the Hazer back up, but it would not budge. It was now stuck on the tower. The added complication was that the steel guy wires were loose, so I now had an unguyed tower with a VHF array sitting on it.

I called Bob and he came over lickety-split. After climbing up to the Hazer level, he determined that the tram cable had jumped out of the pulley at the top of the tower. The cable was wedged in the pulley. What must have happened was when the Hazer came to a halt on the tower the weight went off the cable causing it to go slack. When I tried to coax the Hazer past the sticking point by pulling on the guy wires, I yanked the lowering cable out of the pulley groove and snagged it.

To make matters worse, a high wind warning was in effect for the following morning. I simply had to get that cable moving again. I decided I must go up there and try to free the cable from the pulley, so I strapped on my harness and climbed. This presented some obstacles. First, the Hazer does not offer any good footholds. To get around it, I clipped a harness cowtail to a tower rung just above the Hazer, grabbed hold of the rung with both hands, and pulled myself over the Hazer using my upper body strength. In case you're wondering...YES...that was scary! Then I climbed through the elements of both antennas and gingerly worked my way to the top at 40 feet. When I got to the pulley, I verified the cable was stuck between the wheel and housing. I was far more concerned, however, with the sickening way the unguyed tower was moving around with me at the very top of it. It was probably only moving a few inches, but it was enough to get me extremely nervous. I hugged the tower with one arm and tried to force the cable free. With the full weight of the array on the cable, however, it was hopelessly stuck. I climbed back down and prayed the storm would not be severe. Well, it wasn't and everything survived.

I'm not sure how much of a risk I took by climbing 40 feet of unguyed Rohn-25 with a pinned base. I never felt like the tower was about to break catostrophically, but who knows how close it was? I will admit I experienced the 'shaking leg syndrome' that mountain climbers sometimes get when they are in a very exposed position. To calm down, I took a few deep breaths and double-checked that I was securely tied in.

I formulated a more reasonable game plan at that point. I wedged a 2 x 4 beneath the Hazer and a horizontal tower rung. With the weight of the Hazer and array off the cable, I snapped it free with bolt cutters. Then I tied 3 rope guys to the permanent anchor points and attached them to the tower at the 30 foot level using carabiners. This operation was still pretty nerve-racking until I got all the ropes tight. With the tower much more secure, I went back up to the top and unbolted the pulley assembly. Here is a picture of it on my kitchen floor with the cable still stuck in it. I was stunned to discover that the pulley wheel is aluminum, with only a very shallow groove for the cable. Here is a photo of the wheel after drilling out the riveted pulley axle. You can see where the cable galled up the side surface when it forced its way past.

Bob supplied me with a vintage military aircraft pulley -- this one rolls on a sealed bearing instead of a bushing. And of course it's made of steel. I installed it on the top of the tower using the original Glen Martin (steel) bracket. The original cable was still in decent shape so I routed this through the pulley and down to the Hazer where it was anchored in place. Tension was put on the cable and the Hazer moved upward! The 2 x 4 and temporary rope guys were removed and the antennas were finally at ground level again where the SWR problem was found and fixed. Before returning the Hazer to the top of the tower, all the Glen Martin roller wheels were removed. I now have easy, glitch-free raising and lowering of the antennas.

The whole episode played out over the course of about two weeks. I was back in operation just in time for the Spring 2004 meteor scatter rally.

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