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Old June 20th 06, 01:36 AM posted to rec.radio.amateur.antenna
gravity
 
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Default 5/8 wave for 20 meters


"Rob Roschewsk" wrote in message
. ..
Hi gang,
I'm trying to think of a new antenna for 20 Meters. Had a thought of a
5/8 wave vertical up the side of the house. My calculations tell me this
would be about 41+ feet. Couple of questions:

- is this a good idea?
- can I do it without radials, I'm thinking ground stake, inductor, 41
feet of wire straight up, tapping the inductor at the 50 ohm point with
coax.
- I attempted to model this in NEC2 and for 5/8 at 20M I'm getting an
impeadance at the base at about 7.4613E+01-4.3625E+04j. Does that seem
likely or is my model broken?

Looking forward to what you all think.


i've only made one 5/8 wave. i hear a cap works well since the antenna is
overlength and thus inductive.

you need radials too. my 5/8 wave didn't do too good, i suspect too many
trees, and not enough radials.

Gravity

Thanks,

-- Rob