[NLRS] 432 ARGH

[Bill Davis]

  Hello all
   Well ... Wed night all was fine on 432 (as far as I know) when working VE4MA, VE4DDZ and VE4CY in the RAIN. I swung the beam south when Chris VA3ECO started looking west. Then it occurred to me that Chris and I had not worked. After verifying that Chris did want to try, I again swung the beam north.
   This is where "all was NOT fine" begins. About the 5th or 6th sequence to Chris, the 4CX250 amp screen protection relay started to trip. NOT GOOD. 
   Since it was late and Chris and I were not doing any good, I swung back south for W0GHZ sked on 10GHz, 1296 and 902. Before I went to bed, I quickly fired up the 432 amp again, still tripping the screen overload with drive. I reduced drive and no tripping at 150watts out vrs normal 250w.
  It is raining today so I revisited the issue .... What I discovered was the the amp was tripping due to excessive SWR. With 160watts forward 30watts reflected!!!! Normally if a see a needle width reflected it is a surprise.
  Late last fall, I discovered higher than normal SWR on 1296. What I found was that my (normal foam dielectric) 9913 rotator loop jacket had aged and cracked leading to water egress. I guess that is what I fear here since the age of the rotator loops is the same (2021). The BIG problem is that the 432 antenna is the top antenna of the stack at 68ft. In order to gain access, the rotator must be removed and the rotating mast must be dropped down inside the tower as SIX other individual boom clamps are loosened in order to reach the mast extension that the 432 is attached too. Then the 432 antenna can be removed and the rotator loop can be replaced.
  I have explored bucket trucks etc in the past and the best I have found is 60ft (that is assuming a 6ft reach above the work platform). CRAP 
  I have some thinking to do now. At 82yrs of age this is a bugger. It will require doing all of the above and replacement of the loop and then all in reverse. So many trips up and down. The 432 antenna is my 20yr old (or more) beloved K2RIW 19 elem yagi. 
  What to do ??? Before I do anything I will have to verify the hardline to the top of the tower and do an inspection of the 9913 to see if I have visible jacket / connector problems within reach. The hardline connector junction is inside a innertube rubber boot, so well protected. 
  As I said ARGH
73  Bill K0AWU
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