[TowerTalk] 402-CD vs. EF-240X

Charles H. Harpole harpole@pegasus.cc.ucf.edu
Wed, 29 Apr 1998 18:04:10 -0400 (EDT)


My single band 10, 15, and 20 beams (HyGain 5 el) are much quieter than my
removed TH-7.  And all the new ones are plumber's delight!  de K4VUD

On Wed, 29 Apr 1998, Kenneth D. Grimm wrote:

> >It's the same electrical design with a lot of
> > hardware improvements including 90-100 mph wind rating, phillystran truss,
> > insulated reflector (using the same hardware pictured in the X7/X9 ads),
> > and a balun.  
> 
> This comment got me to wondering what the advantages of insulated
> parasitic elements on a beam are.  Tom, of Force 12, whose antennas use
> insulated parasitic elements on yagis once commented that if you
> believed that by removing the insulation and directly grounding the
> elements to the boom, in plumber's delight fashion, would produce a
> quieter antenna, then go ahead and do it.  My question is, why have
> antenna designers decided to insulate anything other than the driven
> element in the first place?  Has anyone actually bothered to test the
> idea that grounding the elements of a yagi produce a "quieter" antenna
> than one with the parasitic elements insulated?
> 
> 73,
> -- 
> Ken K4XL
> grimm@lynchburg.net
> Boatanchor Manual Archive - ftp://198.28.36.115/pub
> 
> 
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