[600MRG] [Lowfer] Could my antenna be a very large Dummy Load ? - Long Reading

[jrusgrove at comcast.net]

Andy

>Later on, I added a 4th top wire. This one unfortunately is running at a heavy 
>sloping angle and is very close to earth over much of its length.

Sloping top hat wires 'shade' the vertical element and reduce the 
vertical's effective height. The steeper the angle the more the 'shading' effect. You would  be better off with shorter top hat wires that run perpendicular to the vertical element ... even though it would mean more L in the loading coil. Ground losses will dominate your system anyway.   

Jay W1VD  WD2XNS  WE2XGR/2

p.s. Rolling out a number of lengths of chicken wire for the winter made an effective ground system at this location. 


----- Original Message -----
From: Andy - KU4XR via Lowfer <lowfer at mailman.qth.net>
Reply-To: Andy - KU4XR <ku4xr at yahoo.com>, Discussion of the Lowfer \(US, European, & UK\) and MedFer bands <lowfer at mailman.qth.net>
To: 600 meter group <600mrg at w7ekb.com>, 1750 Meter lowfer list <lowfer at mailman.qth.net>
Sent: 10/12/2017 12:56:15 PM
Subject: [Lowfer] Could my antenna be a very large Dummy Load ? - Long Reading


Greetings Gents: 

I am beginning to wonder if I am approaching a Giant " Dummy-Load " with my antenna. I have 4 top load wires,
ranging from 100 feet to just over 200 feet. 2 of the top wires have a termination wire connected between them.
I estimate that I have close to 600 feet of - close to the earth ( 25' 
AGL ) Horizontal wire in the air, and just 
purchased another 750 feet, with the expectation of adding more top wires, and 
termination wire where possible.
I will never have a Ground Radial system that will amount to anything, so 
nothing but mother earth underneath
the top load wires. My Vertical height is 30 feet, and I hope to go up to 40 
feet. That will be about all I can do.
The next comments are based on watching my S-meter, and listening to background 
noise and believing that
I am improving the antenna. ( I know the more vertical height, the better, but 
I am limited ).. 
Here's what I 
have noticed. In the past I had a 160 OCF up 30' AGL - strapped 
as a " T " antenna. It was as noisy as a nascar
race. The short leg, went across the powerline service entrance - tied off to a 
tree. Constant powerline buzz.
I decided to tie the center, and shield of the coax together at the dipole, and 
bend the short leg in another
direction - away from the powerline. Instant reduction in line buzz ! - AND - 
reduction in received signal
levels also. A previous question on this list informed me that powerline 
coupling effect is an issue, thus 
the loss in received signal strengths when I moved the wire away from the 
powerline. But not living with 
a constant 20 over S-9 line buzz was worth a reduction in signal strength. The 
S-meter dropped to S-9 after
moving the wire. No noticable change in the needed L to peak the antenna. I 
added a 3rd top wire, 
and right away saw a difference. After adjusting for Less - L ; the S-meter was 
resting on S-8. Signals
on 630 meters got better. Later on, I added a 4th top wire. This one 
unfortunately is running at a heavy 
sloping angle and is very close to earth over much of its length. Another 
instant change ! After adjusting 
for less - L ; the S-meter was resting around S-6.5 to S-7. What was the short 
leg of the OCF was 
lengthened to within 3 feet of the pine tree limb it is tied off to, and I 
connected a termination wire from
it, over to the heavily sloping wire ( 65 feet ). This is what I have in the 
air at the moment.. After adjusting
for Less - L again, my S-meter is now resting on S-5, and bouncing up to S-6.5 
on peaks. I have not been 
using a Shunt element until just the past 3 weeks or so. Through 
experimentation; I added a Shunt - LC on
the radio side of the loading coil and after adjusting; the S-meter rose 1 S-
unit on resting noise and now
rests at S-6.5 and bounces to S-7.5 on peaks. The level varies due to 
neighborhood noise makers, and when 
it is " dead quiet " , the S-meter rests at S-5, and bounces to S-6.5, BUT, 
that is not the norm unfortunately.
Here are my present values - measured as best I can do. (( Starting point was 
the OCF at 
30' AGL, and 
260 feet top load... I used 152 microHenries of coil with no shunt element ( my oversight there ). ))
The present setup is 30' 
AGL Vertical APEX, with very close to 600 feet of top load wire going in 4 
directions,
and varying land slopes. My Series " L " is 82 microHenries, and the Shunt LC 
on the radio end of the coil
is 93 microHenries - L ( Fixed ) , and 1,142 pF - C ( Air Variable ) . Of 
course, Dryground - Wet ground does
affect the tuning. *** NOW The Big Question for me is: with all the losses over 
earth - no radials - and 
everything else lossy that can be factored in; when I eventually try to put RF 
into this Monstrosity; will I 
possibly be transmitting into a Very Large - Dummy Load ? It Hears, and pretty 
good in my opinion, but,
that doesn't mean it will radiate RF in the same fashion. My hope is to add 3 more top load wires, and 
terminate the ones that can be. I am starting to wonder if this may be an exercise in futility.
Thanks for reading this, and comment if you wish - on the list might be good - for others to benefit from it.

73: Andy - KU4XR Friendsville, TN. - EM75xr
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