Aloha again from Kauai,
Well, with my new MFJ-259, I am finding out all sorts of things
about my antenna/feed line systems!
Thought I would post the Z's of the various Gladiators as seen
from here in the shack at the LMR coax input end. They look
good to me, but I am not an expert at interpreting such.
These taken after the various apparent losses reported
in my previous posts to the reflector.
Am a little puzzled about the rather wide frequency range
over which some of the verticals show X=0 in the impedance
read out, see below:
TL160 Now have a lot of vines covering the vast reaches of the 126
foot long radials; result seems to be a lowering of where I
had set the lowest vswr frequency:
f= 1.760, R=100 ohms, X=0, vswr=1.9:1
f= 1.790, R= 82 ohms, X=17, vswr=1.7:1, lower?
TL80 Radials also have some vines, but have cleared some.
f= 3.46, R= 76 ohm, X=0, vswr= 1.4:1
40 meters unit, radials clear of vines, but hover just above many bushes,
f= 7.014, R= 56 ohms, X=0, vswr= 1.0:1, reactive part reads 0 and
vswr stays at 1.0:1 between 7.0 and about
7.043.
30 meter unit, radial situation same as the 40 unit; vines and bushes just
below by inches, or less.
f= 10102, R=43, X=21, vswr= 1.6:1
f= 10392, R=34, X=0, vswr= 1.4:1, somehow resonance has gone up.
20 meter unit, radial high and clear of vines.
f= 14004, R=53, X=0, vswr= 1.0:1
f=14100. R=59, X=0, vswr= 1.1:1, note, X=0 all the way up from
14000.
f=14195, R=57, X= 16, vswr= 1.3:1
15 meter unit, radials high and clear of everything, but nearby to a
guava tree.
f= 21010, R=53, X=0, vswr= 1.6:1
f=21058, R=84, X=0, vswr= 1.6:1
f=21295, R=41, X=14, vswr=1.4:1, lowest vswr in this band
10 meter unit, entire unit above roof of house, radials, all clear,
70 feet of LMR400 feeding via balun at base.
f=27909, R=54, X=0, vswr= 1.0:1 and these numbers remain constant
up to f=28013, R=56, X=0, vswr=1.0:1
f=28495, R=77, X=0 (!), vswr= 1.4:1
IN fact X=0 is the reading continually from 27909 on up to 28678, where R
has increased to 80 ohms, and X has at last come on at 6 ohms.
So much for the apparent feed Z's as seen here in the shack. When the rains
stop, will go out and measure all at the bases of the Gladiator at the input
terminals of the units as supplied.
73, Jim, KH7M
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