[NLRS] 70-cm Antenna Dilemma

[Ray J]

are you sure your RX is ok...

50 miles should be easy on a wet string with 100 watts... is there a 
mountain between you and the other guy?

i run a 19 element k1fo homebrew and it measured out at the expected 
gain on the range.. i run 100 feet of old 9913 and 10 watts with a old 
ic-451 and work almost all i can hear

W9RAY
Ray





Carl Estey wrote:

>In the Spring of 2005 I obtained a used 16-element 432-Mhz yagii of un-known
>design.  When I got it up on a 40’ tower and fed it with 65’ of LMR-400 I
>found performance over a 50-mile path very poor.  Last week I put up a 48’
>piece of Andrew 7/8” Heliax and a 15’ LMR-400 Ultraflex jumper at the
>antenna the best I can do on a fifty mile path with 100-watts at both ends
>is 20-24 db above the noise – somewhere there is a loss of 40-50 db!!
>Physical exam of the antenna shows nothing wrong, which makes me think the
>balun is the problem – and it is a ½ diameter six-inch long tube that is
>sealed (soldered) on the end with the female N-connector.  One the opposite
>end of the balun from the N-connector are flat zig-zagged metal straps that
>go to several of the elements.  Does anyone recognize the design of this
>16-element antenna and have any specs on it?
>
> 
>
>Yesterday someone loaned me a 25-element 17’ 5” long K1FO-style yagii.  I
>tried the same path with similar poor results.  Adjustment of the T-match
>failed to provide proper SWR at 432.1 and the lowest point was at 430 Mhz
>despite a large amount of re-adjustment.  The measurements (made mostly in
>the dusk so forgive small errors) are as follows:  
>
> 
>
>
>NLRS at mailman.qth.net
>http://mailman.qth.net/mailman/listinfo/nlrs
>
>
>
>  
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