---> QUAD BAND END FED HALF
WAVE WIRE ANTENNA. -- VE3AB
Earl Andrews just put this up 22 Sept
2014 -- with some modifications
based on the old PAR EF 40-20-10
and my own ideas of my own.
|LNR Precision Quad band End Fed Half Wave Antenna (it just came out on the market around July 2014 and I ordered one
right off the bat! - This antenna covers 40,20 and 10 just like the EF 40-20-10 but can handle 200 watts. The 40-20-10
version..with the loading coil..worked real well in my city lot installation..but I like to run 100 watts from time to time and QRP
(especially during QRP contests and operating activities)..so this new QUAD version is the real ticket for me!
- Modified for 4 band coverage: 40 meters, 20 M, 17 meters and 10 meters. Two Driven Elements: a loading coil 39 ft long for
40, 20 and 10 (from my old Par EF 40,20,10 25 watt antenna) and a separate 17 mtr element that will be in parallel with the
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|First of all.. THE QUAD BAND VERSION LNR
Precision antenna came with a precut element
with tuning stubs.
I set that aside for now. -- I wanted to use the
old 39 foot loaded element from my PAR EF
40-20-10 meter antenna for the three bands 40,
20 and 10 AND.. I wanted to add a parallel
element.. (LIKE A FAN DIPOLE does) to cover 17
You can see the coil in the picture as it goes up
in the air towards the top of the tower. The end
insulator is also visible.
The 17 meter parallel element is visible below
the main element.
This is just a TEMPORARY TRY OUT of the
YOu can see the jpg sketch below of the final
configuration I want to use and have for this
|Above: the sketch of what I want this new LNR Quad Antenna to be configured as. I want the separate 17 mtr element to be sort of parallel to the
40-20-10 element..so that (perhaps) on 17 meters..the other non active element may act (perhaps) as a reflector and enhance the radiation (a bit) in
the direction of Europe.
When operating 20 meters.. the now non active element (17 meter element) may act as a passive director in the direction of Europe.
This is the best case scenerio. I dont know if this will happen or not. -- Even if it doesnt act this way.. I will have an antenna that will be reasonably
effective and will allow me to operate on the 17 meter WARC band for the first time from my little city lot in Elliot Lake, Ontario Canada.
|The matchbox/feedpoint will be near the wooden fence at the edge of my yard.
If you look carefully..at the far left of the picture is my other HF antenna - a 40
meter full size quarter wave vertical.
Pictured right is the coax cable going up to the matchbox. It is RG-8X foam
coax but is buried in an irrigation tube.
|In its temporary position.. the resonant frequencies appear to be 24.314, 15.866, 21.067, and 6.4 mhz.
I will start on the 40 meter element by trimming the 33 foot length before the coil. The coil and tag end worked well previously in
the EF 40-20-10 antenna and I am assuming the tag end is about the right length. I will trimi the 33 ft section by about 8 inches or
so to see how that plays..then go from there trimming bit by bit and observing the SWR using my MFJ-249.
I will get the antenna (about right) then I will work at positioning the antenna elements and then (as the last step) ..I will do any
final adjustments to get the SWR curves as best I can.
|Below pictured are some other pictures of the "Temporary" initial installation. It is Sept 23 2014 and the leaves have started
turning. Before too long..winter and snow! - I want to get this antenna up and running soon.
I will be using it this winter and in the spring.. I may go out and buy a good chunk of new low loss coax (more heavy duty than the
|I weather proofed the drainage tubing using a funnel type of
arrangement made from
electrical tape and gas line antifreeze small containers. I
taped everything up so that there would be no leaks.
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|24 September 2014.. NOW..today..I made some changes. The feedpoint has now moved from near ground level to up at the top of the tower
mast..AND.. I have raised the tower mast up to around the 39 foot level. -- The 17 meter band element was spread out from the other
multi-band element and now seems to be acting like a proper 18 mhz antenna. I measured the swr near 1.2 to 1 around 18.4 mhz (see the
pictures below). Won't take much to get the swr down around 18.100 by tagging on a bit more wire. The other SWR readings on the
40-20-10 meter element were a bit dissapointing. See the pictures and discussion below -->
|I raised the metal mast up the tower and the top of the
mast with the LNR QUAD match box is up around the 39
foot level. I have a pulley and rope and can raise and
lower the antenna. Also..I have a second rope and pulley
arrangement at the top of the mast and I may put up a
second end fed antenna (perhaps for 6 meters) later in
Ideally.. I would like a 6 or more turn loop of coax at the
LNR matchbox..but the coax length would not allow this.
Later on..I may put an extension piece on the coax.
|The 17 meter element. See swr reading on the MFJ
analyser below. Swr is pretty good. I will tag on a few
inches of wire at the end of the element and it should
be perfect. How it will perform on the air..who knows?
I had good results with the PAR ef 40-20-10 and I
expect results should be good with this new version
|6.22 mhz is sort of in between 7 mhz and the newer 60 meter allocations around 5.5
What should I do? Leave it the way it is and use a tuner for 7 mhz operation and
probably try it on 5.5 mhz? - I do have a remote automatic tuner the LDG RT-100 that I
could mount up near the feed point and tune it remotely. HMMMM!!! I will think about
this possibility! I dont want to burn out that LNR matchbox with a high mismatch and 100
watts. The loading coil (from the old EF-40-20-10) looks like it should take a bit of abuse
as well..but I dont want to take chances at burning it out either!
|Here is the other resonant point. I think this should be
the 14 mhz band but instead it is low SWR near 16 mhz.
As for 28 mhz.. the SWR is not dipping down anywhere
around 28 mhz..so.. maybe some action is necessary.
ANOTHER THING I COULD DO.. is TAKE OUT THE
LOADING COIL. I think I will do this in the next day or
two. -- I am going fishing tommorrow but maybe the
next day I will take out the loading coil. It is bolted on
to the element and is easily taken out.
Then I will be left with an approximate 33 foot element
which should (hopefully) resonant on 20 meters or
With any luck..it will also resonate as a 1 wave (high Z)
antenna on 28 mhz.
As for 7 mhz..I have a 33 foot vertical that can cover
that band. With a tuner..I can get the 33 foot antenna to
easily work 21 mhz as the 3rd harmonic.
|The far end (near ground)
supporting rope for the ends
of the antenna is not rope at
all but rather blue weed
wacker line. It works quite well
and sort of blends in with the
Up at the antenna..I use black
UV proof Dacron Rope I
bought from a ham radio
|Initially.. I put the matchbox at the low end of the antenna (near ground)..but
I did not like the looks of things ..so I put it up the tower the next day and it
looks better and might perform better. It is surrounded by too much clutter
down near ground level and to make adjustments to the length of the
antenna elements.. it is better the ends of the elements slope down towards
the ground where I can more easily reach them. -- As well.. I can add
extensions at the end or ends to try out other bands by adjusting the
lenghts. This LNR matchbox is broadbanded and will cover all frequencies
from 40 mtrs through 10 meters.
To the 17 meter element..I may tag a length on (from time to time) ..so that I
can work 30 meters. Perhaps I can have a clip on/clip off extension that
allows me to change configurations rather quickly. -- These are all things I
|THIS FIRST attempt at a multi band version..FAILED -- MAJOR
PROBLEMS: 1) swr curves not good. Interactions occured
between a each of the 2 wire elements. When the wind was
blowing..you could see the swr moving around. Too unstable
SWR would not bottom out low enough. What I did is Oct 2
2014 - I cut off the 18 mhz element and put the antenna back up
with only one wire element - about 32 feet long or maybe a bit
less..now there is good low SWR reading on 20 meters and 10
SEE NEW ARTICLE 2 OCT-14 CONCERNING THE LNR
PRECISION "QUAD BAND" VERSION MATCHBOX. LINK HR
|I tried a few things - 1) placing the match box near ground
level and running the wires up to the top of the tower.
I decided to go back to having the matchbox at the top of the
tower and mast. I could then "trim" the wires or perhaps
even add a wire piece on - without LOWERING MY ANTENNA
WITH THE PULLEY AND ROPE.
2) I tried 2 parallel elements (like two parallel elements of a
dipole) with one feedline - attempting to have 1 separate
element for 17 meters and the other element would cover
40, 20 and 10 -- IT DIDNT WORK AS THE 2 ELEMENTS SEEMED
TO REACT WITH EACH OTHER AND THREW THE FEEDPOINT
|The separate 17 meter element worked fine but the
other element for 40,20,10 was all screwed up.
When viewing the SWR analyser..with the wind blowing
the SWR meter would "bob around" and things just
Anyways.. thats all part of the game. Experimenting and
trying things out! I went back to a SINGLE RADIATING
ELEMENT configuration and the new article and story
is now available at this LINK.
|Thats it for this experiment with the LNR QUAD band antenna (End Fed Half Wave-
Multiband antenna (100 watt version). I have re-configured the antenna with only
ONE single radiating element -- and it is now working much better. This new article can be
read at this LINK HERE -- thanks for looking at the experiment! -- Just because it didnt work
for me..doesnt mean you can't get it to work (somehow!!) -- 73 Earl VE3AB
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