[TowerTalk] Force 12 Sigma 180 80M dipole

[StellarCAT]

Steve,

I would bet your not expanding the coil far enough. Mine was expanded to the 
point that the end of the coil itself was OUTSIDE the connection point! In 
other words the distance from one connection point to the other was LESS 
THAN the length of the coil! This is what it took for me. The ends are 
bolted and I feel strongly that this is needed in order to maintain the Q of 
the ckt.

Not to ask dumb questions but I am one that believes in not making 
assumptions - you do have the hairpin at the bottom of the relay box and not 
at the antenna correct? That of course would not cause infinite vswr but is 
a valid question nonetheless. I am not sure of your description below - you 
say hooking it up with the balun, relays, hairpin it does not work - but 
hooking the balun up to the feedpoint works - huh?

g.
K9RX


  ----- Original Message ----- 
  From: K7LXC at aol.com
  To: towertalk at contesting.com ; Force12Talk at qth.com
  Cc: RXDesign at ssvecnet.com
  Sent: Sunday, March 04, 2007 8:09 AM
  Subject: Force 12 Sigma 180 80M dipole


  Howdy, TowerTalkians --

      I'm installing one of these antennas and have run into a problem that 
I need some input on. The antenna natural resonant frequency is 3.500, it 
should be about 3.800. The manual is pretty ambiguous (nothing new there) 
about the coils; it looks like the outer end connects to a thru-the-element 
bolt. A similar one I installed was not fixed and used U-bolts to vary the 
length of the coil along the element. It seems like we should try that on 
this antenna. Gary, K9RX, has one and used the attachment to the thru-bolt 
successfully so now I'm confused.

      Also, when I have the relay box, hairpin coil and balun hooked up, I 
get infinite SWR which is a typically a feedline problem. Hooking the balun 
directly to the feedpoint works as it should. More confusion. :-(

      TIA for any help.

  Cheers,
  Steve    K7LXC
  TOWER TECH





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