Its not just for safety. Typically, a 1/4 vertical over a reasonable
radial system will have a low input impedance of about 25-30 ohms. The
coil shunted across the input raises the input impedance to match the 52
ohm coax.
I used #12 vinyl coated house wire wrapped around a broom handle to
create the form. Then just prunned it a turn at a time till I got a
nice match in the middle of the band.
Go for it,
dave
wa3gin
Lee Buller wrote:
>Liberal Arts Major type of question.....
>
>On some verticle antennas (i.e. Butternut) there is a
>coil between the feed point and ground. The coil is
>about 1 1/2" in diameter and about 10 to 12 turns. I
>think it is used for a DC ground return for
>lightening. Then again....I may be wrong.
>
>If I was to fabricate my own 1/4 wave verticle...is
>such a thing needed for safety since my verticle I am
>planning does not have an actual ground-ground...but a
>ground plane instead. I would say the the antenna is
>going to be a 1/4 wave ground plane.
>
>Lee - K0WA
>
>
>In our day and age it seems that Common Sense is in short supply. If you
>don't have any Common Sense - get some and use it. If you can't find any
>common sense, ask for help from somebody who has some common sense.
>_______________________________________________
>
>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.
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
>
_______________________________________________
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.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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