An inverted L without radials is a random length wire and the
measurements are of no meaning until there is a ground system to make up
the other half of the antenna.
But to Wes point, the 259 and big 160m antennas is a recipe for going
nuts. You don't even need a high powered BC station - even a low
powered station a pretty far distance away can cause the 259 to give
results in error. A VNA or something like the Rig Expert are FAR more
robust in this application.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 8/21/19 12:04 AM, Wes wrote:
How many high-powered BC stations do you have around?
Wes N7WS
On 8/21/2019 8:55 AM, N4ZR wrote:
I just put up an inverted L, with a vertical length of about 60 feet,
and a total of 135 feet. It is fed through 16 turns of RG-400 on a
ferrite core at the base. There are, as yet, no radials.
Because I was impatient to see what was going on, I grounded the
shield to a single copper-plated ground rod and connected my MFJ259B.
I expected a high R value, and I got one - 112-122 ohms. But
surprisingly (to me), lowest SWR was at 2.070 MHz, and X remained at
zero over quite a wide range - all the way down to about 1.7 MHz.
Is this all to be expected? I plan to put down at least minimum
radials in the next few days, and would expect the R value to drop as
I do so. Am I off-base?
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