>
>Chuck: Quads are capable of a much better F/B than equivelant boomed yagis.
>A 2 el quad can obtain in excess of 30 dB f/b. The problem is, very few
>spend the time (And it is a lot of time) tuning.
>After playing with a lot of quads, I have the following "User Observations".
>1) Adding additional bands to a single set of spreaders complicates tuning
> a lot. At least doubles the tuning time.
>2) I believe it is vertually impossible to properly tune a 4 element quad.
> The interaction is unbelievable.
>3) At a given boom length and height, the quad wins, hands down.
>
>4) If you can keep it in the air in Anchorage, you're a better man than me!
> But, I'm gonna put another up next summer, anyway!
>de KL7HF
I have really tried not to jump in here but can't restrain myself any
longer. Additionally let me add my remarks are totally biased and are in no
way objective! I have been using quads for 42 years now and you can flame me
with thermite and napalm I ain't about to listen.
I currently have a 4 el quad on a 30' boom. I also have a KT-34xa at a
second QTH. The KT-34 is like a rotatable dipole in comparison. The FB and
side rejection just don't compare. I also interlaced 12/17 on the two
directors of the quad for 2 el on those bands with no real interaction
detectable.
In addition to the observations by KL7HF above let me add a couple:
5. From a crank up tilt over tower (triex) I do all my quad work alone, from
a 10' step ladder, in my driveway. I would NEVER tackle a 4el with a guyed
tower unless my brother-in-law owned a crane.
6. Never again would I put one up in an area which has ice storms.
7. Always feed each band individually with a switch that shorts unused
bands. Also use a 1/4 wave stub of 72ohm coax between driver and switch.
8. Stick with tried and proven 7 strand hard drawn #14 copper. It ain't fun
restringing 1000' of wire some a--hole sold you at a ham fest as the
latest/greatest silky smooth crap. Been there done that. Also use Rod's
1004/fmhz for element length.
9. You guys quit telling folks how good they are! If everybody used them I'd
be sitting in the pileups for hours.
Lastly the beauty of a quad is how well it HEARS, in all weather. The KT-34
gets thru fine, so have the TA-33s I've used, IF I can hear them. I got a
phone call duing the Peter I operation when I worked Tony on 15m, asking me
what I was smoking, from a top notch dxer with stacked yagis, when I spotted
Tony on the cluster. Forty minutes LATER others were working him. Quads open
bands and close them.
Cheers and see you in the Heard p/u
de Ed W4EP aka AB4PY
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