So.... has anyone else done a mix where the Philly (PS) was less than 50% of
the total length? I did a bunch of modeling and found using simply a 50’ length
of PS at the tower for the bottom 2 sets of guys and 70’ for the top one
provides no worse than 2 db degradation of the FB (and most of the directions a
good bit less). (note in all the modeling the FB was the first victim, SWR is
the next and it takes more to effect it – gain is way down the list hardly ever
effected by more than about 0.2 db.)
BUT ... how do you tension this?! Since PS requires an initial set of 15% of
full tension and EHS needs 10%! Do you start out at say 12% and see if it
‘relaxes’ to 10?
And anyone know of any reasons why you’d need to go to the next size PS? They
say if the PS length is less than 50% it should be the next size up! I’m
planning on 5/16” EHS for the top guy – that is 11,200# PS ... the next size up
is 15,400# (and probably twice the price ... $5/ft?...more?!)
Thanks
Gary
K9RX
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