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Re: [TowerTalk] Help in planning a new QTH

To: Steve London <n2ic@arrl.net>
Subject: Re: [TowerTalk] Help in planning a new QTH
From: Jim Jones K0HY <k0hy@comcast.net>
Date: Wed, 16 Mar 2005 09:16:43 -0700
List-post: <mailto:towertalk@contesting.com>
For me the Steppir has too many moving parts way up the in the air.  
Anything mechanical will break sometime, and if it moves it will break 
quicker.

73  Jim

Steve London wrote:

> From Dave Hachedorian's (K6LL) posting:
>
> > Once you do the conversions, the claimed
> > gain is as follows:
>
> > Band    4el Steppir    C31XR
> > 20        9.5dBi        8.1
> > 17        10.0            -
> > 15        10.2          8.4
> > 12        10.4            -
> > 10        10.6          9.5
>
>Those Steppir gain figures are very questionable.  They are significantly 
>higher 
>than the gain figures for optimized yagi designs in the 20th edition of the 
>ARRL 
>Antenna Book.  While a Steppir may be a fine antenna, it's still just 4 
>elements 
>on each band, and won't be any better than an optimized 4 element beam on the 
>same boom length.
>
>For another comparison:
>
>Band   Optimized 4-element from ARRL Antenna Book
>
>20            8.5 dBi (26 foot boom)
>17            8.5 dBi (20 foot boom)
>15            8.2 dBi (18 foot boom)
>12            8.5 dBi (15 foot boom)
>10            8.3 dBi (14 foot boom)
>
>Now, you could argue that the Steppir has the 4 elements on a longer boom, so 
>let's compare to an optimized yagi with approximately the same boom length:
>
>Band        Optimized N-element yagi from ARRL Antenna Book
>
>20           9.2 dBi (34 foot boom, 5 elements)
>17           9.8 dBi (30 foot boom, 5 elements)
>15           10.8 dBi (36 foot boom, 5 elements)
>12           10.8 dBi (30 foot boom, 6 elements)
>10           11.6 dBi (36 foot boom, 6 elements)
>
>I would have to conclude that the Steppir manufacture's gain figures are 
>inflated on 20 and 17 meters.  I would also question the higher bands - when I 
>get a chance I'll have to model 4-element optimized yagis for 15, 12 and 10 
>meters on 32 foot booms and compare to the Steppir claims.
>
>By the way, I have done my own modeling of the C31XR vs. optimized yagis.  The 
>model and results are at http://n2ic.topcities.com/c31xr/c31xr.htm .
>
>73,
>Steve, N2IC
>_______________________________________________
>
>See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless 
>Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any 
>questions and ask for Sherman, W2FLA.
>
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>
>  
>

_______________________________________________

See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless Weather 
Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any questions 
and ask for Sherman, W2FLA.

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