Hi All:
I knew I would draw a few tough critics on tower talk. I do not have a 33
million dollar test range. All of my testing is hands on comparisons. I just
moved to another location and all of my towers are on the ground. Before, I
had some very good Yagis in the air. 8 over 8 over 8 over 8 on 10 meters. A
fantastic array. These antennas were designed by W2PV. One 24' boom five el
Quad 70% of the time outperformed the Yagis. The Yagis were stacked at 35',
70', 105' and 140'. All were active 100% of the time.The Quad was on my test
tower at 55'. On 10m only KB4I with two stacked Quads could out perform my
Quad. Again this was only one series of test that were conducted. I know
Yagis and Quads and have studied all data since 1972 that has been available
to me. BTW Quads will stay in the air as long as Yagis if they are
engineered properly. OK, Lew could get carried away, but once past this
point he knew more than you or I will ever know about antennas, tuners, TVI
etc. I had a Ham in upstate Maine that had one of my antennas. All of his
Telrex antennas came down in a winter storm, but the Quad survived. I will
be glad to send you a copy of the W1ICP eff. article that was published in
CQ. You might find it interesting without preconceived opinions. Just check
the references at the end of the article. I will mail it to you free if you
promise me you will read it with an open mind. Anyone else wants it I will
send it to them. One question ? who discovered electricity.
Bill Wall KC4UZ Antenna Mart
----- Original Message -----
From: "k4oj" <k4oj@tampabay.rr.com>
To: "Bill Wall" <billwall@eyecon-solutions.com>
Cc: "Jon Ogden" <na9d@speakeasy.net>; "xppq" <xppq@pyramid.net>;
<towertalk@contesting.com>
Sent: Saturday, November 16, 2002 2:41 PM
Subject: Re: [Towertalk] IS Boom length the HOLY GRAIL ?
>
>
> Bill Wall wrote:
>
> >Consider the full wave Quad has about 1.8 db more gain than a 1/2 wave
Yagi.
> >
>
> where is this from?
>
>
> >The Quad is quieter on receive and does not hear rain static.
> >
>
> a given, while I have never done a side by side this is an agreed upon
> benefit og the quad
>
>
> >The efficiency
> >of the average 3 el Quad is in the 90% + category.
> >
>
> sez who?
>
> >The 3 el Yagi is about
> >50%.
> >
> sez who??
>
>
> >Put 1000 watts on the Quad and you have apprx. 900 watts. Put 1000
> >watts on the same Yagi and you have aprrx 500 watts out. The power is
lost
> >in resistive heat.
> >
>
> I assume these are based on the above presumptions
>
>
> >A few years ago Lew Mccoy W1ICP published an article in CQ magazine about
> >this.
> >
> ...uh oh - time to put on the boots
>
> >Boom length is gain, but there are other things that are more
> >important like, takeoff angle, frontal lobe pattern and so forth.
> >
> >
> Finally I agree with you, Bill - but where do you get those gain and
> efficiency percentages?
>
> The folk lore I heard whilst walking up the hill was that having a quad
> versus a yagu was like buying an extra element - if you had a 3 element
> quad it was like a 4 element yagi - except for the maintennance which is
> vitrually nil for a correctly built and installed yagi...so...build
> yagis with more elements to offset the advantage the guy with the quad
> had and don't have to deal with the numerous maintennance issues a quad
> represents!
>
> 73,
>
> Jim, K4OJ
>
>
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