The 34 ohms is the sum of Rr (antenna radiation Z over perfect ground)
and Rg (ground R loss). Rr depends on the dimensions of the L plus a
bit of wire loss. My guess is Rr is about 10 ohms less than 34 ohms,
some easy modeling will determine it.
Then it is a question of what antenna efficiency you want vs cost and
time for more radials. If 10 ohms is Rg, then about 1/3 of the TX power
is warming the worms.
Grant KZ1W
On 11/12/2022 07:31, ws6x.ars@gmail.com wrote:
In my experience here in "ROCK"ingham County, I didn't reach the point of
diminishing returns until around 32 radials of varying lengths (Most were either 50 or
100' long.). Much would depend on length, configuration, terrain and ground conductivity.
Jim - WS6X
-----Original Message-----
From: Topband <topband-bounces+ws6x.ars=gmail.com@contesting.com> On Behalf Of
Pete Smith N4ZR
Sent: Monday, November 7, 2022 4:27 PM
To: topband reflector <Topband@contesting.com>
Subject: Topband: How good is good enough
Now that the lawn mowing is done for the season, I resuscitated my 160M
inverted L. With 13 on the ground radials, each roughly 70 feet long, measured
R of 34 ohms seems OK to me. Is it worth laying down more radials, or am I
approaching diminishing returns?
--
73, Pete N4ZR
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