Towertalk
[Top] [All Lists]

[Towertalk] IS Boom length the HOLY GRAIL ?

To: <towertalk@contesting.com>
Subject: [Towertalk] IS Boom length the HOLY GRAIL ?
From: k4oj@tampabay.rr.com (k4oj)
Date: Sat, 16 Nov 2002 14:41:48 -0500
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



<Prev in Thread] Current Thread [Next in Thread>