[Antennas] Krazy Antenna Idea

2002年5月01日 15:42:47 -0700

Ahh .. finally .. the Empower has no clothes Thanks, George .. that is such
a neatly written response I have seen hams waller around trying to get
their ground mounted / ground buried radials laid out to "resonant"
frequency .. HAR .. t'ain't there, when you lay that waarrr on/in the
ground! Unless you are laying on silica (sand), and, note even then, ain't
resonant!!!! Now, not to say a 2 foot radial will work like a 65 foot
radial on 75 meters, BUT .......... 73, Mark .. retired broadcast
engineer .. AA6DX
----- Original Message -----
From: "George, W5YR" <[email protected]>
To: "Chris BONDE" <[email protected]>
Cc: <[email protected]>
Sent: Wednesday, May 01, 2002 2:37 PM
Subject: Re: [Antennas] Krazy Antenna Idea
> Radials that are in contact with the ground are detuned by the ground and
> need not be resonant. They are there to collect return currents within
> about 1/4-wavelength of the base of the antenna. Length is not critical -
> the more the better.
>> Radials that are elevated need to be resonant to be effective. That means
> that their length is critical as are their surroundings. They cannot lay
on
> something like a carport roof that would detune them. They cannot be
> connected to ground or anything except an insulator at the far end. Snow
> will probably detune the radials, perhaps substantially.
>> A radial that starts out in the air, runs along a roof and then dives down
> to be connected to ground is not really a radial but an extended "ground"
> wire that is too long to have much effect.
>> I see little need to elevate the antenna for 160. Put it on the ground and
> put out as many radials as you can of whatever lengths you can fit into
the
> property. More shorter radials are better than fewer longer radials. Snow
> will have little effect.
>> I would forget about the carport . . .
>> 73/72/oo, George W5YR - the Yellow Rose of Texas
> Fairview, TX 30 mi NE of Dallas in Collin county EM13qe
> Amateur Radio W5YR, in the 56th year and it just keeps getting better!
> QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771 I-LINK 11735
> Icom IC-756PRO #02121 Kachina 505 DSP #91900556 Icom IC-765 #02437
>>> Chris BONDE wrote:
> >
> > I have been planning on being on 160m. The upper portion, say 1850 to
1975.
> > I have a carport that runs E-W, that is the length, the mountain to the
N
> > fairly well prohibits propagation that way.
> >
> > If I mount a vertical on the N side of the carport, run the radials E-W
on
> > the N edge, S-E and S-W to the diagonal corners, and, S on the width,
with
> > possibly, the radials from the N wrapping along the edge to join the
> > diagonals which could go to the ground and be grounded, along with the
> > width N-S going to ground over the edge. This is the first question how
> > would that work for the radial system? How would the snow on the roof
of
> > the car port, up to 4ft deep, dry and wet, influence the radials plus
the
> > antenna. Now that is something else.
> >
> > __________________O________________________
> > ! / |
> > \ |
> > | / | \
> > |
> > etc
> > Any comments on this radial system?
> >
> > Chris opr VE7HCB
> - - -
>> Your moderator for this list is:
> Larry Wilson KE1HZ [email protected]
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