I once had a 4el 20-15-10 homebrew Quad, built from
a QST article back in the early 70's/late 60's. It was a
real performer. (Yeah, yeah subjective, etc etc.) The
only problems were that I didn't use large enough
AL tubing for the spreaders (1" irrigation) and not
large enough solid copper wire (#14). All on a 3" AL
boom. The spreaders were broken up with Delrin
insulators.
Yes! I had a tilt-over tower and a 10ft step ladder for
maintenance. Still have those.
I took it down in 1983 after a severe ice storm and replaced
it with a TH7DXX which is still up. No issues except that the
20m section resonates up in the phone band with 1:1 SWR
and I don't use phone if I can avoid it.
If I decide to build another quad, I would use something like 1.5" tubes
to start off with and #12 copper-weld wire and use solid HDPE
for the insulators, drilling tiny holes in the AL tubes where needed
to allow condensate to drain.
73,
Charlie, N0TT
On Fri, 20 Jun 2014 11:17:56 -0500 "John Langdon"
<jlangdon1@austin.rr.com> writes:
> IMHO quads very good antennas - they are very cost effective, they do
> hear a
> little better and are a little quieter, but, you should live in an
> area with
> no icing issues and have a tilt over crank up tower in a location
> that
> allows you easy standing access to make repairs, because they will
> be
> required! That said, the last time I had a quad was 1969! :)
>
> 73 John N5CQ
>
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf
> Of Bill
> Parry
> Sent: Friday, June 20, 2014 10:43 AM
> To: 'Herbert Schoenbohm'; towertalk@contesting.com
> Subject: Re: [TowerTalk] 10 throu 20 beam traps or no traps
>
> Herb,
>
> Joe is exactly right. I have used quads extensively. I have had two
> different 2 element quads and one 4 element quads. I will grant you
> that
> they may hear a little better but they are WAY TOO MUCH TROUBLE. I
> finally
> gave up the ship and moved to antennas that go up easily and stay
> up. I
> admire you for sticking with them for so long.
>
> Bill W5VX
>
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf
> Of
> Herbert Schoenbohm
> Sent: Friday, June 20, 2014 9:50 AM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] 10 throu 20 beam traps or no traps
>
> 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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