Spring Antenna Service 28 - April - 2013Posted by k9zw in A Good Read series, K9ZW, K9ZW Just Rambled, K9ZW Shack.
Tags: Diversity Reception, slipp-not, Tennadyne, Tennadyne Anntennas
This winter and early spring have not been kind to outdoor equipment.
This weekend finally the weather broke and it has been nice enough to spend some time on the antennas.
Original plan was to do a lower, inspect, service & repair in a few weeks, but some obvious impact from exceptionally high winds has made it prudent to start now.
The two log periodics are on the same mast, and winds have tweaked the larger (T-8 10-20m) about 5-10 degrees from the upper smaller (T-28 1.3ghz-6m) most likely by slipping the larger boom.
My T-8 predates the “Slipp-Not” brackets that Tennadyne offers and a set will be on order (I make pick it up at Dayton). This should reduce the chance of one antenna slipping in relation to the other. Beam Width coverage is wide enough the little tweak is more an offense to me than it is to performance, so it may wait until the next lowering.
My Tri-Ex/Tasjian Tower has feedline stand-offs that I user large UV resistant o-rings as the cable retainers in the forked ends of the stand-offs.
Wind and time took out the second from top o-ring and the wild winds caused the feedline to be hooked about the clamp. It is amazing to think how wild of wilds would be needed to raise that much triple-coax-feedlines-plus-rotor cable around enough to whip it about – must have been a monster wind.
The cable is not hugely at risk, but it would be better to get it back in place. Again I will have to decide if I deal with it now or in a few weeks.
When the tower is lowered and tilted over I use a set of scaffold I bought from work – a handful of rings from a manufacturer long out of business that don’t connect with any other brand (not that you should). Useless for work but just what I needed and makes an ultra safe work platform.
WHen it comes down next the coax seals will all be inspected and renewed as needed, each cable gets a visual and wipe down, plus gets a check with the TDR for any electrical problems.
I have upgraded lightning protection that will get installed.
A decision to be made is whether to swap out the rotor (a Ham-IV) for a freshly overhauled Ham-IV or whether to leave well enough alone. Plan was to swap in the fresh overhaul and then have the long serving unit overhauled as the spare.
Decisions will hing on whether I can disengage the displaced cables for now (I lower the mast but haven’t tipped it over yet) or whether I need to hand crank the tip-over now.
It is also time to get the buried feedline in to do a second HF antenna on most bands. Originally I was going to make the vertical just another setting on the remote antenna switch, but I am now thinking it should be on the second feedline to the shack so two can be used at the same time. The Flex-5000A could use the dual antennas now and the Flex-6700 will take the diversity capability to a new level if I get my antennas sorted out correctly.
At least it is warmer out once I figure out the plan!