Perhaps your right Joe....but tri-band quads deserve better
consideration as I think they are getting a bad rap. Below in bold
italics is my rejoinder.
On 6/20/2014 9:13 AM, Joe Subich, W4TV wrote:
Why not many serious DX-ers and contesters consider Tri-band or even
Five-band quads is a mystery to me.
1) survivability - quads are much more fragile than yagis with regard
to icing./*(Certainly not a problem here in the tropics*//*)*/
2) survivability - wire flexing tends to cause premature failure in
windy environments /*(Good wire less problem and in 75 MPH winds no
breakage yet after 3 years with stranded #14 high quality.)*/
3) difficult to handle - a flexible three dimensional structure is
difficult to get on to a tower, particularly a guyed tower. /*(With a
two wire 45 degree boom tram and leaving the center element out it is
very easy keeping the wire away from the guys while erecting the
antenna. I string the center element(s) on the tower by spinning the
inside hub and using precut wire.)*/
4) poor performer - the structural/survivability problems make very
long boom quads particularly problematic rendering quads uncompetitive
against very long boom yagis. /*(A three element quad with fiberglass
spreaders withstand impact and wind gusting that crack off aluminum
elements and if ever broken very easy to repair with a splint and some
FG repair compound.) Performance of a three element quad on a 20' boom
is equal or better than a 4 element mono bander*//*on even an optimum
boom.*//*Plus it has better band coverage which is a real concern for
some amps that just trip out at 2:1 VSWR.
*/
The added dimension also makes it difficult to stack quads. /*(Who
would ever want to?*//*)*//*Again super monster beams and stack are in
a totally different category. i thought we were looking for a good
subsitute for trap antennas and the problems they present and the lack
of performance they are stuck with?)
*//**/
All that aside, a two or three element quad can be an effective
alternative to a basic trapped tribander if the user has an unguyed
tower and lives in a benign environment (most don't <G>).
73,
... Joe, W4TV
/*Please also consider the lower Q Quad with less static build up with
passing TS or even snow static that occurs just when that new country is
peaking. Where the quad hears what the yagi doesn't. Some claim that
like all loops the random noise is less. This seems to be the case here
but admittedly could be wishful thinking. I must admit that my low
quality mast cracked and the quad fell as far as the top guys during a
wind storm. (I was using fencing for the mast...my bad.) Yet the wires
snared the quad and after the first calm day the quad was taken apart on
the tower and reassemble on the ground with new wire. This time I used
insulated wire and the quad immediately stopped working well. (I never
took in consideration the Velocity Factor of the two different wires.)
Also many aluminum beams that would take such a hit may be be toast with
a bunch of bent aluminum tubing.*//*
Herb, KV4FZ
*/
/**/
On 2014-06-20 8:17 AM, Herbert Schoenbohm wrote:
Three bands no traps and great performance the three element Cubex Quad
wins hands down especially for price and wind load. Plus with proper
matching 75 ohm stubs on 10 and 15 I get both CW and SSB coverage below
1.5 to 1 over the range. Why not many serious DX-ers and contesters
consider Tri-band or even Five-band quads is a mystery to me.
Herb Schoenbohm, KV4FZ
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