Dan, NEC-2 shows a 2:1 VSWR bandwidth of 70 kHz for your antenna and that's
with a zero ohm ground. You should be seeing about 90 kHz.
You might check it after dark when the AM BC stations reduce power. Your
Autek might be over loading.
Dave WX7G
On Dec 15, 2011 12:44 PM, "Dan Bookwalter" <n8dcj@yahoo.com> wrote:
> Ok , on to my next dumb question ..... I now have 12 radials anywhere from
> 125-250' long , as expected my SWR went up , so I lengthened the horizontal
> part , the overall length is now about 175ft (72ft vertical). I added an
> air variable cap (not sure of the value , but , it worked great at another
> QTH) and set the SWR on my Autek RF1 to about 1.3:1 at 1835 , came into the
> shack and the swr was essentially infinite. When I went back out to the
> tower I checked the impedance with the RF1 and it was about 560 Ohms , so I
> then decided to set the impedance to as close to 50 Ohms as I could , I got
> it down to about 68 ohms at 1840. Now the SWR is 1.6:1 at 1840 , but , the
> 2:1 swr bandwidth is from 1823 to 1858 , that seems a little narrow to me ?
>
> Suggestions ?
>
> Dan N8DCJ
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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