[TowerTalk] Wonder how 4El Gem Quad compares to other 4El Quads?

K7GCO@aol.com K7GCO@aol.com
Fri, 7 Sep 2001 02:51:45 EDT


In a message dated 9/6/01 10:11:08 PM Pacific Daylight Time, poster@gate.net 
writes:

<< 
 I'm just wondering how they compare in performance??????
 
 Jack
  >>
I presume you are interested in comparisons with current 80/75/40M verticals. 
 The present ones weren't around when I used the HT-18 Hy tower.  It did very 
well for me on 75&40M and I based loaded it to 160M.  I had to raise the Z as 
it was about 20 ohms or so.  I added a Xc across the feed point of such value 
with it resonated lower that it gave 50 ohms.  It worked well but it had 
narrow bandwidth.

I then modified it top loading it to a 1/4 wave on 160M.  On 80/75 it was 
then a 1/2 wave electrically and a 1/4 wave physically which was matched with 
an L network. On 40M it was a 1 WL on 40M electrically and 1/2 wave 
physically and matched with an L network.  It worked far better this way on 
all three bands.  The Z was higher but still not 50 ohms and I used the Shunt 
Xc again.  The details are in a CQ article I wrote about 35 years ago.  I 
have 2 other versions (Mark II & Mark III) now.  k7gco

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