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PA5COR
05-12-2009, 09:06 AM
I know, the Island is addictive :mrgreen:

I'm running an OCF (Fritzel FD- 4) with coil and 30 feet of extra wire from 160 to 10 meters.
For 15/12/10 an rebuild old Imax 2000 vertical on the roof.

But, since my activities on 160 picked up in the winters, and my abstention from the Zed offered hours to fill, the weather was sunny and fine, i decided it was time for something new.

A real vertical for 160 was out of the question, the lot i live on is just 100 x 25 feet...

Sitting here, frustrated, was of no help, so back to the idea books, ARRL RSGB antenna books, and Karl Rothammel.

Using my H.T in the workroom, ( transceivers are at ground level in the living room) to keep contact on the local repeaters my eye fell on the nifty rubber ducky......

A 10 watt bulb went on ( i,m a known dimwit) and an idea was born.

In the last years i "planted" lotsa copper wire in the garden in the front and back of the house, added a star configuration of 5 copper rods 10 feet long for the earth for the station, a 6 feet long wire connects that to my ground rail on wich the components, transceivers tuner, SB-1000 etc are grounded, and the earth for the house is also connected to that.

In the DIY store i got a PVC rainwater pipe, 1 3/4 inch in size, 20 feet long.
In the shed was a piece of surplus wood, 8 feet long, wich fitted nicely in that PVC pipe.

Add 50 meters, or 170 feet of copper wire, wich was wound on the pole, spaced about 1 inch apart.

I had 3 ring cores here, 4C65 iron core, Mu 125.
Use super glue, stack them, and make a 1:9 balun out of it.

Add together, we have a vertical that works from 160 up to 10 meters, and maybe more.
SWR is quite low, the tuner had no problem making a match ( MFJ 993-B)

To test if i didn't make a dummy load, i tested it with the gang on 160 meters, comparing it with the FD-4 at 45 feet above ground ( young sea clay)

Result, 8 dB less signal as the FD-4, receive was reciproke.

The vertical had LOTS less static/noise in reception, where i could not hear the other station with the OCF, the vertical pulled them in no problem, 1 to 3 S points less stronger as the OCF but with much less static and noise.
Making it possible to hear a station on the vertical, that was completely covered in the noise on the OCF.

This was the case on 160/80/40.
Even on 20 the noise was less, but here the OCF remained top antenna for reception, being 1/2 wave above ground here.

Worked a few countries on several bands, running 100 to 500 Watts into that vertical.
The balun went up 5 to 10 degrees Celsius with 500 watt input depending on the band/SWR. nothing to be worried about.

Results, sometimes almost same S points in the reports back, sometimes 1 to 2 S points less, depending on the antenna/polarization of the other station.
This is just preliminary, further tests over a longer time are needed.
The balun is connected to the ground system at the feed point, the ferrite clamps were left over and used "just in case"

Cost:
8 Euro, PVC drainpipe.
15 Euro for the 3 4C65 iron core ferrite ring cores.
A grab in the junk box.

Result:
working antenna
Tons of fun.
Lotsa surprised peeps that though " it won't work" but it does....

PA5COR
05-12-2009, 09:08 AM
Blast
Forgot antenna piccie :roll:

On top is a top hat made of copper wire.
diameter about 20 inches...

PA5COR
06-07-2009, 01:40 PM
Final setup
13.55 meters high
110 meters wire aluminium 2.6 mm
Top hat 4 x 50 cm.

PA5COR
06-07-2009, 01:42 PM
Detail winding

W2NAP
06-07-2009, 07:38 PM
i like.

i have to redo my receiver antenna now due to the storms last weekend

PA5COR
06-08-2009, 01:25 AM
First tests are positive.

Antenna that i use to compare it with is a Fritzel OCF with coil and 30 feet of wire to make it resonant on 160 meters, at 45 feet above thee ground.

In most cases the vertical is the winner, certainly above 300 miles distance.
Groundwave is stronger as well.
Fed with 12.5 to 50 Ohm unun, homemade.
Tests with an Belgian station at 300 miles away with a full size vertical at his side shows a definate preference for the vertical.

Cost 80 euro.

:D

PA5COR
06-09-2009, 03:19 PM
Sight from below

PA5COR
06-09-2009, 03:21 PM
The result on the analiser

As said, fed directly with coax, no balun.

Also working on 14 MHz, 24 MHz, and 10 M, but it is my main 160 M antenna, next to the lengthened OCF.

W5GA
06-10-2009, 11:28 AM
You've got a lot more patience than I have to wind that much wire on a pole! It will be very interesting to see how it performs on TB come winter.

PA5COR
06-10-2009, 01:23 PM
The winding of that 110 meters/350 feet of aluminium wire cost me 2 hours, with bare hands and regular coffee breaks.

For Europe the Jury is still out, sometimes the vertical is better, sometimes the lengthened ocf.
From 1000 km's or more the vertical mostly wins.
The next winter will bee decisive, looking forward on topband to the experiments.

The near field, up to 50 miles, the groundwave vertical is lots stronger., wich should tell me that the take off angle is low(er).

Just tested it with 1 KW and it is performing fine.
Keeping animals and people away from the exposed feeeding point needs an solution though.
No interference of any kind in any electronics was found.

Have to do some other things first, but the pole will be getting a few sidearms, on wich an 80 meter vertical, linear loaded, and a full size vertical for 40 will find their place.

The pole was made of ex army glassfiber poles wich can be extended ( 4 feet long) each section.
I used 9 of these, 10.80 meters and the junkbox provided the 2.75 meters of glassfiber ex Diamond vertical section, tophat made of 4 brass 2 feeet long spokes.
Total length 45 feet.
On the picture taken from below you can see the long section of the OCF running 8 feet next to it.
And 3 guy wires of wich one with an eye bolt on the roof for supporting the antenna when i let it down alone, and put it up again.
Still left with 700 feet of that aluminium wire :D

;)

Cor

W2NAP
06-10-2009, 02:58 PM
how dose it receive thu all of HF.

PA5COR
06-11-2009, 02:40 AM
It's made for mono bander work, 160 meters.

Receptionwise it works as a long wire ;)

The normal Zero Five designs of 45 feet aluminium pole fed with a current 1:4 balun are totally unusable on 160, just usable on 80 and only start to work decently from 40 and up.

Even then they are not the DX gun as claimed, i know, it was one of the first i made here for testing...


The 160 meter 45 foot long antenna does better as the OCF wich was lengthened and at 45 feeet above ground.
Reception on 80 is 3 S points lower as the OCF, but from 40 and up very decent, the 110 meeter long wire acting as just that, a coiled up 110 meter long wire.
Get the DOS based program Helical3.exe, you can design your own, in any length from 20 feet and up.

Worked a Polish ham, mobile, a few Italians, all better on the vertical as the OCF.
If you put an autotuner at the base it will work fine from 40 meters and up, better as the zeo five configurations, as i tried that with my MFJ 993-B at the base of both antenna's.

But with a few sidearms and a linear loaded 80 vertical and a full size 40 meter vertical it will do excellent on 160/80/40, and up.

The soil i live on is very conductive young silty seaclay, in the ccourse over the years i put in 12 groundstakes for grounding, and about 2000 feet of excess copper wire for the ground radials.

Daily contact can be made with a Belgian station both running QRP ( 2 and 5 watts) over 300 miles, he is using a full size 160 vertical, 37 meters high, and me using the 45 footer.
There are no miracle antenna's and no decent all band verticals.
This was made for 160, anything extra was nicee, but not designed for.

By winding an 1/2 wave wire on the vertical the feed point impedance is higher as a 1/4 wave wire, so the loss against ground is a lot lower.
But you still need a good ground, there is no substitute for that...
You can use elevated radials, but here i opted for lots of copper in the ground.
The aluminium wire is 2.8 mm in size just over 1/10th of an inch.
Used here for electric fences, and quite cheap.
And under 1/3 of the weight of copper :D.

Using the same vertical and the folded back 80 meter vertical and full size 40 meter vertical on the same structure and 2 relais you can switch between the 3 verticals, using the same structure and ground.

The lower angle of radiation will add DX to the low bands.
Our plot is just 100 by 30 feet wide....
So up is the only way to go for me.

The mast i made is hinged at the base, i can drop it alone, and erect it alone, changing the configuration as i like.
The 45 foot length is chosen as maximum length without getting the neighbours panties in a wad, certainly if you look at the antenna farm on the roof .... :roll:
Diamond X 510
23 Elements Flexa 70 cm yagi
11 elements Flexa yagi 2 m
5 element 6 meter yagi
OCF FD-4 lengthened for 160 meters 180 feet long at 45 feet above ground. 160 - 10
Rebuild Imax 2000, 15/12/10
Diamond discone for local 2/70 work
Homemade 6 feet long wifi antenna
45 feet long 160 vertical, with in the future 80/40 vertical sections added.
Station:
2 Yaesu Ft 847, Collins filters and modified.
Yaesu FT 100 mobile transciever
MFJ 993-B auto tuner
EQ plus
MD-1 Microphone on boom
Heathkit SB-1000, new RF parts 3-500ZG
Homebrew transistor amp 250 watts, 2 meter
PSU's homebrew 40 to 90 amp
Several switched PSU's SEC 1223
Ameritron ARB 704 switcher for the Amp
Daiwa CN 801 active PEP SWR meter, and a bunch Diamond HF 2/70 meters
Lots of other transcievers, for the van, H.T's and lots of other junk.

Coax Ecoflex 15, extreme low loss 1/2 inch foam.
N connectors throughout the system, PL259 only on HF.
The standard measuring equipment, scope antenna analiser and whatever you need building stuff.
As ex pipefitter/TIG welder a whole bunch of tools, angle grinder welding machine, etc.

And lots of fun building my own stuff.
One reason the masts on the roof are made of 316 stainless steel thickwalled pipes, up through all storms the last 18 years.
And a very uunderstanding wife.... :roll:

kq9j
06-11-2009, 09:48 PM
I enjoyed your story and it was very thorough with plenty of detail on construction and performance.

Last fall I put together a 40 meter vertical using 6 of those 4-foot military mast sections. The wire is wound in the same helical fashion. I have worked more DX on that vertical on 40 than I ever had before. And that's with only 4 radials on the ground.

Tomorrow I am finally going to be able to go to my favorite building supply store about an hour's drive from here and among other things I am coming back with a big spool of wire. The back yard will be mowed short and I will lay a lot more radials down.

I put the thing up just for fun and didn't really think it would work that well...but it sure has. I can't wait to see how the improved ground system helps.

PA5COR
06-12-2009, 03:16 AM
No substitution for a vertical to work DX or it should be a good beam ;)
With the littlee size plots we have here that is out of the question, so the verticaal it is.

The antenna is a development thingy, i abandoned the paralel dipole idea.
Now there will be a outdoor watertight box, with relais and LC arrangements for 80/40/20 to get the full antenna working on those bands, i tried that out in the program, and that would work better as the paralel dipole idea, wich would detune the others.

Main advantage, i can do all the work at ground level, now i need to find a good size watertight box, a few decent variable C's and the coils can be homebrew.
I could opt for a autotuner, but i want to be able to put the full output of the Heathkit SB-1000 on it, so separate band matching sections will be the way i will follow.
Even without matching sections in place, reception on other bands is fine, and sometimes the difference of making out a station, or not beeing able to hear it.

Whenever i find some spare copper wire it gets buried in the garden and connected to the radial field zigzagging, straight, in any form i can fit it in.
For the shorter bands you might opt for the elevated radials.
The hight is good, 45 feet is manageble, we do live within 25 miles of the North Sea coast, and you can understand we do have some prettty strong winds up here sometimes.
The ground here is young seaclay, so resistance is low already..
But as for any vertical, ground radials are the way to go.
Thanks for the feedback, really appreciated ;)

Now working 6 meter, Ukraine is booming in :D

PA5COR
08-16-2009, 02:57 PM
Last addition

Fed now directly with 50 Ohm coax.

SWR is 1: 1.5 as expected the ground losses add a better picture as it should be.

Directly fed and resonant on 1.850 mHz it is 1/2 to 1 S point better as the OCF.

As it is now, it is a monobander for 160 meter, after the winter period and trying a compare with DX with the ocf antennna, i'll decide to make it into a 60 feet mulltiband antenna fed with a 1:4 Unun.

I tried it with the 45 feet length, and 1:4 UNun, but on 160 and 80 it was disappointing, on 40 and 30 and 20 quite good.
:cheers:

PA5COR
02-24-2010, 09:00 AM
Changed the 160 meter vertical.
Added 2 wires at the top, each 40 feet long 180 degrees from eachother, had to shorten the helical section in windings, more spacing and less windings of course.
Look at it as a helically wound vertically fed T antenna against ground ;) ( getting a headache here :snicker: )

Back to resonance at 1850, added some left over copper wire as RF ground, now about 1000 feet total, different lengths and most within the 100 x 25 feet plot of land the house is on, and 4 wires at the top ends going away from that as an H , the antenna is roughly in the middle of that.

Looking good, less losses through the smaller numbers of helical windings, ( about half of the original) the current is getting up higher from the ground.
The vertical section is 13.6 meters high, or 45 feet helically wound ALU wire 2.8 mm ( 0.11 inch) about 40 meters in length in a wide spaced helical pattern, spacing at the bottom is larger as higher up.

To my surprise the antenna now also works on 40 meters....??? direct fed with 1:1 unun with coax at the bottom of the vertical.
Tested with 100 - 1000 watts here, no RF problems here. ( Heathkit SB-1000 new 3-500ZG tube.

Hope we get some nice spring weather introducing an auto tuner at the feedpoint, lets see what that does.

N9FE
02-24-2010, 09:23 AM
http://www.smeter.net/slc/slc.php Check your results here

PA5COR
02-24-2010, 11:50 AM
Useful link already in the favorites as the Dutch and Swiss remote receivers.

Already worked Canada and the US on 160 with it, it might not be the best antenna, but for the space i have it does work.

Ogling a tree 100 feet away, municipally owned, but a thin grey wire......Inverted L ?

N9FE
02-24-2010, 11:51 AM
They will NEVER know... Shhhh

PA5COR
06-15-2010, 12:37 PM
Since the weather was good the last weeks i have spend some considerable time with my 50 foot mast on which the helical 160 meter antenna was made.

I took the helical down, went to an inverted V antenna, 1/4 wave 50 foot vertical, the rest sideways to the streetlantern at 21 feet high.
Then i made the inverted L 3/8 and used a sturdy variable C to tune it back to the 1850 KHz we normally operate.
The radial field stayed the same, now 1400 feet of wire in the ground, and several earth points 10+ feet deep copper stakes.

The results were all down from the helically fed T antenna...

So, down the mast went today, the old helical coil was put back on, and the top capacity is 2 x 6 meters ( 20 feet) of copper wire with insulation.
Sloping down from 50 feet at the top, back to about 35 feet above ground, something like the umbrella antenna.

Results, 2 dB gain more as the inverted L antenna which was maximised in it's working.
Running the SB-1000 from Heathkit, the 1000 watts didn't let the televisions, or other consumer electronics budge, no interference whatso ever.

Worked in daytime some stations including my friends which i use for comparison of the antenna's and all confirmed the helical was minimum 2 dB up.

The analizer did show some good results.
Rs 50 Xs 10 Swr 1.4, from 1810 Swr 2.0, 1891 again 2.0.
Will take some more pictures.
Next: Magnetic loop antenna 12 feet from copperpipe octagonal for 160....

Will keep you informed of my d*cking around...;)

WØTKX
06-15-2010, 12:55 PM
I have two 3.5" by 48" heavy shipping tubes that are just SCREAMING to be coil forms. :mrgreen: I'm thinking remote tuner, and maybe switchable taps as well.

Your experiment makes we want to go that route, instead of the HF2V that was practically given to me for under $50.

Lot here is 60 x 100, long axis runs E-W :( But I can use my neighbors trees... she gave me permission.

She's not there anymore, bad interior fire, not enough insurance... abandoned house now.

PA5COR
06-15-2010, 05:33 PM
You have more space as me ..... my plot is 100 feet by 25 feet, that's all...
The helical is a oneband antenna, just now in qso with G7KLJ, he runs only 30 watts and the helical puts in a 3 dB better signal as the inverted L.

I use the streetlantern in the front yard to string a few lines to ;)
Will make a few pictures to show the setup.
Your idea sounds good, though i don't like coils in antenna's to lengthen them, too lossy, even top loading coils, i'd rather use tophats or top wires to load up the antenna's.

take care,
Cor

WØTKX
06-15-2010, 05:45 PM
Yea, I need to put up a big "T Marconi" and see how low it loads up. And get better with EZNEC. :yes:

If the lot was rotated 90 degrees, I'd try a reversible wire Moxon on 75/80.

PA5COR
06-15-2010, 06:24 PM
got piccie:

WØTKX
06-15-2010, 07:03 PM
So, what kind of roof mulch do you use to grow metal RF flowers like that?

BTW, your signature line is elitist. ;) :lol:

PA5COR
06-16-2010, 02:26 AM
;)
The large vertical in the piccie in the middle starts at the groundlevel, 50 feet up, you can't see the 2 top hat wires clearly but they are there.

Doing some calculations and the efficiency of the vertical is 78% more or less compared to a full size vertical for 160 meters.
You caan make out the 5 element 6 meter beam, the 11 element 2 meter flexa yagi and the 23 element flexa 70 cm yagi.
The Diamond x 510 is above that.
On the left is the reworked Imax 2000 with 5 meter radials i was given, it now works fine on 10/12/15/17 as vertical.
The OCF ( Fritzel FD-4) with coil and wire for 160 is barely visible.
Time for a radio day, then back to the working table for a magloop for 160.

Who said you can't make a reasonable antenna for 160 meters on a small plot?

:chin::)

VK3ZL
06-16-2010, 04:15 AM
Great work Cor....You now have to work me between November and March next year....Looking forward to the S9+++ signal report on Topband...:hyper:

Bob..VK3ZL..

N5RLR
06-16-2010, 08:15 PM
Excellent job, Cor. Any antenna is better than none; that it compares favorably to a full-size radiator is the proverbial icing on the cake. :-D

PA5COR
06-17-2010, 03:25 AM
Thanks for all the nice words ;)
Except for the OCF antenna with coil and piece of wire made fit to work at 160 up, the vertical antenna was the only choice for DX, or a chance of DX.
The city lot i live on is just 100 feet long, 25 wide...

Room enough to go up, and the helical was tried first, going from the principle that winding a 1/2 wave length of wire will raise the radiation resistance, and improve radiation resistance and efficiency.
It worked fine, but with only the OCF antenna to compare it and a few friends with T and L antenna's i decided to test these too.
Off the helix coil went and i put up T and full size L antennas 15 meters ( 50 feet) vertical.
The results were not bad, but looking back over the months use of the helical vertical, something was missing, these L and T antenna's weren't as good as the helical.

So, this week i lowered the mast, and restored the helically wound antenna, with 2 x 6 meter long wires on top for top hat capacity.
The earth radials stayed the same for all antenna's so my personal experience is that this antenna works better local and DX as a L or T antenna with the same hight.
I even tried a 3/8 L antenna to get the current higher up the wire...and less loss in the radial net.
Tests over the last winter till now with UK stations 400 - 1000 km away confirmed the results, each antenna was up at least a month for testing to get some realistic results.
G7KLJ Steve, was a big help in this providing many reports and listening to my ramblings on antenna's.
(Some help from the book Low band DXing from ON4UN, Rothammel, RSGB/ARRL antenna boooks, and personal experience too)

All tests were done with standard 100 watt, the SB-1000 was not used.

Simply said the antenna is made of 9 glass fiber sections of 4 feet length each 1 1/2 inch thickness used in the army for putting up camo nets.
Total length 10.80 meters on which 100 meters of aluminium wire is wound ( always wind some more on it for pruning it to get it resonant)
That wire is sold in several thickness in agricultural outlets for fencing wire, i chose the 2.75 mm wire just over 0.1 inch thickness.

On top of that i made an topsection of 4.20 meters with 20 mm aluminium tubing and the last part a glass fiber top.
The top section has a simple wire running straight up that section to the top, where 2 wires of each 6 meters are connected as top capacity hat.
An elaborate ( 400 meters) of copper wire went in the ground filling every nook and cranny of the 100 x 25 feet city lot, several 40 meter long wires over the fence, and to the front of the house.
The ground net of the house was connected even the kitchen sink ( stainless steel) is connected to that.
Living on good conducting ground, young sea clay, i get decent results, even living on the edge of the town.

Feeding it directly with 50 Ohm coax, a few clamp on ferrite's at the feed point around the coax to keep RF from the outside of the coax.
Pruning it with the MFj analizer at the feedpoint, taking off windings to get it resonant in the part of choice for you at 160 meters.

Bandwith here between 1:2 is around 100 KHz.
Since we only can operate from 1810 to 1880 that is wide enough for the whole band.
Tried the Sb - 1000 on it, and it works fine with full power in it.
No televisions or other consumer goods were disturbed or hurt by that :-D

If you read the thread from the start you get the idea how to go with it, if you want to build one, or just ask and i'll try to answer your Q's.

73,

Cor

Off to make a magnetic loop for 160....:shifty:

Ehhh Bob, i would be happy with a 5 by 2.....;)
All typo's are mine alone...

PA5COR
06-17-2010, 11:07 AM
Done.
Test loop ready and made some qso's with iit on 160.
Just 50 watts before the variable C started to arc...
9 feet diameter, will post piccie later and more results.

:yes:

W4RLR
06-17-2010, 10:54 PM
All those pictures not only give me antenna envy, but make me homesick for The Netherlands. Oh to be back in that little farm house in Terschuur...

PA5COR
06-18-2010, 01:46 AM
Come back, all is forgiven:-D

My neighbours are quite used to see the most strange contraptions pop up here as antenna for testing.
Since the EEC Law protects my rights as ham to put up antenna's we don't have CCR's and the like.
Any clausule that prohibits masts and antenna's is automatically void.
There are rulrs in place, but i can pretty well put up anything i like.
Since i'm an antenna nut, and my MFJ 269 analizer has to be put to good use, i'll stick to it :-D

As i showed, with cheap and cheerfull stuff you can make your own effective antenna's.
Even living on a small city lot...

Next project, how to make a variable C with unetched PCB for 15 KV, i can buy a vacuum C but this is much more fun to do, and i have lots of nice square meters unetched pcb and teflon strips to make someting from that, prefferably motor driven if the pcb variable C is working.
My attick is 30 feet long, 15 feet high, and 25 feet wide, that should take a decent size loop.

I'll first make a smaller loop for testing purposes, then if i like the results, will go for the big one.
Both should handle the full output of the Heathkit SB 1000.
:pray:

al2n
06-19-2010, 07:36 PM
A great read and a good job on the antenna.

I am starting to plan my antenna for the new QTH and am mulling over a vertical. This thread gave me some great ideas.

PA5COR
06-20-2010, 03:22 AM
Verticals are good for dx, not so good for local ragchewing.
Multiband verticals are always a compromise on most bands..
Full size loops ( 160 or 80 meters) will be multiband use, give good gain and are relative noisefree.
My OCF is just 55 meters long, originally made for 80 and up, added a coil ( 180 micro H and 30 feet of wire) to let it resonate on 160.
Magnetic loops can be costly ( copper tubing, Vacuum C) but if chosen right size, will really perform.

Verticals are noisy in recieve, if you live in a rural buildt up area, be prepared for noise..., get a magnetic loop or full size loop for recieve up.
Ladder line fed dipoles are better for noise as my OCF for 160- 10 and also multiband.
Decissions, decissions..
All powerlines here are burried, except for the 300 and 500 KV lines, in the city you won't find overhead powerlines here.
An inverted L will give dx as well good local signal, having vertical and horizontal components in the transmitted signal.

For verticals and inverted L's a good ground is making or breaking the antenna performance.
Hope you get something up that really works for you.
It is not the transciever or P.A. that does the job, it is the antenna system that does the job.
;)

PA5COR
06-25-2010, 09:02 AM
Latest loop.
11 feet diameter, 41meters 3 mm aluwire and 45 pF condenser value for 1.850.
Was 7 dB better as the one turn loop.

Project still going on, this was just one version with coaxial loop for coupling, another one with triangular wire worked fine also, no piccie of that one.

PA5COR
07-06-2010, 06:34 AM
New step in the vertical.

A friend offered to produce from titanium/aluminium sections of tubing, the same material as Titanex uses, of 7 feet long.

The base is 60 mm tubing the top 3/8 inch.
Full size 80 meter vertical, and the wire will be the inverted L part of the 160 meter section.

The trap is homebrew, with RG 58 coax as C, inside the coil form, dipped to frequency.
Height about 20 meters, made the isolator of good quality insulator.

Just need some good UV resistant guying wire and then it will take the place of the helical vertical.

PA5COR
07-13-2010, 01:01 PM
It's done.

Everyone might have asked him/herself why i have been so quiet on the boards.
partly because i lost interest in politics ( temporarely) and because i had the annually urge to build antenna's again.

The new improved inverted L is up, the vertical part is 19.85 meters high, the rest goes off to the front of the house to the lantern post and then 3 meters in a 80 degree corner to another hang up point.

SWR 1.4, 36 Ohms so need some LC network to make the feedpoint match perfectly to the inverted L

I ditched the 80/160 meter idea, and went back to the monobander idea.

Reports are about 1 S point better in europe aas the old one, give or take conditions.
What i did notice compared to the helically wound antenna is that the angle of radiation is much lower, let's see how that works out...

:mrgreen:

PA5COR
07-26-2010, 07:42 AM
http://www.youtube.com/watch?v=qBnPwIaZ-yg

PA7AVS on his radio talking to our group including me in his farm tractor
I was working on my invertel L as on the oictures above
Calls PA7AVS, PA3BUF, PA5COR, PA5SVD, PA3NGK.
His little transciever went in overdrive with my signal, he is just 10 km's away from me, so his front end overloads.

;)

PA5COR
09-09-2010, 07:20 AM
Did some work on the inverted L antenna.
The 11 x 2 meter sections were with force 8 gale too whimsy in my view.
So, from 45 mm back to 20 mm i opted for new tubing, 10 feet long so that the top section went from 20 to 22 meters (73 feet) and shortened the horizontal section to get back the resonance at 1.850 MHz.

Initial reports on the groundwave 30 - 80 km's away, 2 dB more signal, will take a few weeks to see how it handles the other skywave propagation.
We have a group Dutch and UK stations, including Brian M3LLU who regularly chat and report back.

And no, i'm not going higher, it is a very large antenna between the houses... sticking out like a sore thumb.
The house is 9 meters high, it is 13 meters over that...

PA5COR
09-29-2010, 05:20 AM
Next project, since the 77 foot high vertical L antenna is ready, the EWE antenna.
Here the 1:9 unun.
And the picture of the inverted L.

PA5COR
11-16-2010, 11:12 AM
K, 75 feet vertical, rest sloping down, fed at the base with the MFJ 998 1.5 kW Intellituner, extensive radial field. total length 43 meters, a bit too long for a 1/4 wave, but better for tuning on 1/2 wave and more resonance points, which now are out of band.

Tuning fine on 160, 80, 40, 20, noot tried anywhere else, for that i have another vertical.

Will report back how it holds up with the OCF Fritzel FD-4.

;)

PA5COR
02-12-2011, 03:48 AM
Reporting back then as prommissed.

Worked the USA from east coast to 800 miles in land, Canada, all Europe up to the Chineese border running 400 watts from the Heathkit SB 1000.
Could make more power but decided i would keep to our max power levels alowed here.

The MFJ 998 holding up beautifull, and the inverted L is used on 160 - 20 meter, on 80 it's very good with the max current at the top of the antenna.
Even on 20 switching over from OCF to L there is a big difference, sometimes the OCF is better, most of the time the L has the edge.

It will tune up to 10 meeters though, not really tried there yet.

;)

ka4dpo
02-14-2011, 04:00 PM
Nice job Cor, I like the Balun & you gave me an idea that I can use here. Thanks..

PA5COR
02-14-2011, 04:03 PM
Cheers, if you have any Questions please ask.

If i can, i will help out ;)

73,
Cor

WØTKX
02-14-2011, 07:53 PM
Early this AM, I gave the new loop a try on 160. Touchy, but I can tune there! :dance:

PA5COR
02-15-2011, 05:37 AM
You could lengthen the feedline ( open line) a bit to make it easier tunable ;)
Welcome to 160 then ;)