[TowerTalk] 80 Meter Quad Bandwidth

[K3BU at aol.com]

In a message dated 11/6/03 9:09:44 PM Eastern Standard Time, W5PR at swbell.net 
writes:
>>Two element quad with .15 wavelength spacing one element on each side of 
the tower in a "diamond" configuration (points up, down, L & R) bottom about 10' 
off the ground, feeding the DE at a corner for vertical polarization.

1.  How much might the vertical tower in the middle of a                      
   vertically polarized quad degrade its performance?

2. What kind of a bandwidth should I expect?  Can I tune it for             
3.7 MHz and work from 3.5 to 3.9 MHz?
<<


1. To find out, it would help to model that in software. It depends on 
dimensions and stuff around it. If there were right dimensions, the tower could act 
as "dummy" director like in OWA antennas and widen the B/W.

2. That is normally too much B/W to expect. You could tune it for minimum SWR 
using tuner or matching, but gain and F/B would be off at extremes. Normally 
it is advisable to use loading stub or coils to insert with relays in both 
elements for lower end of the band.

Yuri