Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna

Fri, 13 Mar 2020 12:05:02 -0700 

Duane,
I agree on both points.  The antenna is THE most important element of any station (the accepted maxim is it's 90% of the budget but most hams are 'cheap').  The radio is useless without a decent antenna.  An EDZ can work well but the peaks and nulls vary on every band and wind in the trees can be an issue.  Height matters, a LOT too. 


I also hid (in plain sight) a similar 370' EDZ (at 35') antenna IN the 
HOA space (shot a wire over some oak trees) for years without it being 
seen and it worked well (other than the noise floor was obscenely high, 
all the time because it was urban).  It absolutely ROCKED on 40M (the 
noise precluded hearing much on 160M but I got 15-20 countries).



If budget is less of a concern, you might want to consider SteppIR, 
starting with the 2 element Urban beam (40-6M).  The only other comment 
along that line is leave a LOT of headroom capacity when selecting a 
rotator, they take a lot of wind abuse.  There are other beam antennas 
worth consideration, many are less expensive.



When I moved away from the HOA infestation area into rural with a 40 db 
(average) lower noise floor, in time I went from all band (R7, dipole or 
vertical) wires to a SteppIR DB36/80 (80-6M) which gave me an average of 
another 10 dB of GAIN in reception (plus directivity to null noise even 
further AND transmit gain too).



I bought the antenna, rotor and tower at an estate sale (SK sale), 
saving many thousands of dollars.  The son (a non-ham) just wanted it 
all gone, I assisted ;-) so keep watch, ready to 'attack'.



The sole remaining wire is an Inverted L for 160M.  I greatly prefer 
this to any dipole because the one wire is not pulled/stretched between 
multiple trees when it's windy (and the trees NEVER sway in sync at the 
same moments).  It moves precisely WITH the tree motion, it isn't 
stretched or pulled.  However, it's moderately deaf on 160M, I'll have 
to add an RX array (RBOG or 8 square are the current considerations) yet 
I'm now at 131 countries worked on 160M.



The sole sticking point remaining is my requirement that NOTHING antenna 
can be seen from the house (I bought an amazing view, it came with a 
house), so even with the acres I have, I'm limited to a few acres total, 
further reduced by proximity to the power lines along the road.  
Fortunately my neighbor (700' away) is also an HF active ham with even 
more acres (same visual rule) so we're considering a shared RX array 
(SDR and wifi based, which removes much of the desense issue too).



So my suggestion is that you look at the larger picture and perhaps even 
start fresh, not re-modify the original plans (make it a Revolution, not 
just an evolution).  Part of my move (escape to) here was just for that 
reason, to start with a fresh station based on simplicity of operation 
(which takes a LOT of planning and work to obtain; in a couple years, 
it'll be there, I hope.)


GL,
Rick NK7I


On 3/13/2020 11:19 AM, Lyn Norstad wrote:

Duane -


  


I am of the mind that the antenna is the most crucial part of any station,
and probably the most often maligned.  I have made a number of presentations
to ham groups on the design and construction  process involved in getting
the most bang for the buck, depending on your wants and needs (everybody's
are different).


  


In my own situation (2 acre semi-rural lot approx.150 feet x 600 feet
running E-W feet, and active HOA) the goal was to have a single antenna that
would provide the best primary signal on 80 meters in a North-South
direction, while providing the best possible signal on 40 meters in an
East-West direction, consistent with the 80 meter performance and without
unduly provoking the HOA (or my XYL).


  


I decided on an Extended Double Zepp, cut for 3.5 MHz.  That resulted in a
length of 360 feet, which worked nicely since I have 400 feet clear from the
house (West end) to a perfect tree for the far East end.  And another tree
in the center for support of both the antenna and the feedline.


  


I am feeding it with a 160 foot length of 600 ohm "true ladder line."  I can
go into more detail if this sounds like something that would work.  Modeling
this antenna with EZ NEC shows a maximum theoretical gain of 4.7 dbi in both
North and South directions.  With the ladder line, a dual hybrid balun and
short length of coax into the shack, my KAT500 tunes it very nicely on all
bands 160 m thru 6m.


  


I don't have your call so can't see where you are, but would be happy to
make other suggestions based on the coverage you seek.


  


73

Lyn, W0LEN


  

  


-----Original Message-----
From: [email protected] [mailto:[email protected]]
Sent: Friday, March 13, 2020 11:52 AM
To: Lyn Norstad; [email protected]
Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna


  


Hi Lyn - thanks for the reply!

I have 3 acres of wooded land.

Its pretty much on two different levels.

The house is located on the lower level.

And from there the grade goes upwards about 30 feet- and then levels off to
the second level.


  


Many elm trees which can support an antenna height of about 45 feet.

And I can cut through a path through them if necessary.


  


I have a 40m moxon pointed towards Asia at 45 feet hanging over solid rock

I've made a few DX contacts with it during the years when propagation was
peaking.

But right now I think its really to low to the ground to be useful.


  


I'm interested in what you have in mind.

Thanks

Duane


  


On Fri, Mar 13, 2020, at 12:31 PM, Lyn Norstad wrote:


Duane -
There are other wire antenna options that will far outperform a simple
dipole, or for that matter a 2EL yagi.
How much space do you have available?
73
Lyn, W0LEN
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of [email protected]
Sent: Friday, March 13, 2020 10:38 AM
To: [email protected]
Subject: [Elecraft] Off-Topic: Your advice/suggestion about antenna
 From what I understand - solid rock below a raised vertical is not the

best


option for performance.
With an underlying geography of many feet of solid metamorphic rock - that
would probably rule out the low angle benefits of vertical antennas.
Consequently, over the years, every 40m vertical I've ever put up has been
out-performed by a dipole at .41 wavelength.  I've also tried the DX-Half
Square and vertical Delta Loop with the same results.
It looks to me like my only option to outperform a 40m dipole - is a tower
and (at minimum) a 2EL yagi.
Would that assumption be correct?
Thanks
Duane
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