TopBand: Re: Rohn 25

[Milt Jensen, N5IA]

At 02:50 AM 8/14/97 EDT, Earl W Cunningham wrote:
>Hi, Top-banders,
>
>John, W0UN has informed me that each section of Rohn 25 when installed is
>a net 9' 8-1/2", so here's the corrected info for Phil, K5PC, who wanted
>to know how many sections with a 10' adjustable mast at the top would
>resonate at 1830 kHz.
>
>13 sections of Rohn 25 (126' 2-1/2") with 3' 7" of 2" diameter mast
>sticking out of the top (total height 129' 9-1/2") is 1/4-wave resonant
>at 1830 kHz.  Feedpoint impedance at resonance is 36 + j0 ohms, or


ALMOST PERFECTLY MIRRORS MY EXPERIENCE HERE WITH MY FULL SIZED GROUNDPLANE
MADE OF ROHN 25.  IT IS INSULATED AT 1/8 WAVELENGTH ABOVE GROUND WITH 1/4
WAVELENGTH ABOVE THAT AND FOUR 1/4 WAVELENGTH CAGED, INSULATED RADIALS.  IT
WORKS.  73 DE MILT, N5IA


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