On 1/12/2021 10:48 AM, sawye...@earthlink.net wrote:
Elevated 160M radials really need
to be more like 20 – 25 ft above the ground to be efficient.
Yes, this both my experience and the advice I got from N6BT, who has
done LOTS of work with verticals. N6LF, who has also done lots of work
For a portable helix loaded 160m vertical, I measured 1 and 2 127ft
radials at 3.5ft and 6.5ft above ground (average or worse) and found a
significant difference in the resonance R.
1 radial 3.5ft 50 ohms
1 radial @ 6.5ft 33 ohms
2 radials @ 6.5ft 28 ohms
Which quantified the change in ground
Rudy, N6LF, wrote a great article on his elevated radial experiments.
https://www.antennasbyn6lf.com/2012/02/elevated-radial-ground-systems-some-cautions.html
Rudy says,
"1) Use at least 10 to 12 radials.
2) Make an effort to have the radial system as symmetric as possible.
3) Keep the radial
Mike, All ¼ wave verticals have the same elevation angles. The question is
what is the feedpoint efficiency which is dominated by the ground. That
ground is a combination of your soil characteristics and the radial field
design. In my opinion, 2 elevated radials about 5 ft above the ground is
Awesome. Thank you very much Dave !
Mike, Coreen & Corey
Keswick Ridge, NB
From: Dave Cuthbert [mailto:telegraph...@gmail.com]
Sent: January 11, 2021 5:59 PM
To: Mike Smith VE9AA
Subject: Re: Topband: Inverted J antennas?
Okay, over "medium" GND (0.005S/13) it has the
A
Cc: topband
Subject: Re: Topband: Inverted J antennas?
Hi Mike,
your inverted-J in EZNEC shows a radiation resistance at 1850kHz of 10 ohms. It
is resonant at 1800kHz.
With the 50' vertical wire removed it is resonant at 2.7MHz and has a radiation
resistance at 1850kHz of 11
Hi Mike,
your inverted-J in EZNEC shows a radiation resistance at 1850kHz of 10
ohms. It is resonant at 1800kHz.
With the 50' vertical wire removed it is resonant at 2.7MHz and has a
radiation resistance at 1850kHz of 11 ohms.
Dave KH6AQ
On Mon, Jan 11, 2021 at 10:52 AM Mike Smith VE9AA
Has anyone modeled an inverted J on 160m ? (almost an inverted U, really)
I currently have only one left (the other half of my 2-el array blew down
and I've been lazy to replace it) and it "works" but not as good as it could
I think if I had better supports (ie: taller trees, wider yard). I
