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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