SM7UZY



The end fed long wire project



June 2018 - Updated January 2019


In this article I will try to share my experience with the end fed long wire antenna. The good, the bad..

First of.. I am not a mathematician that calculate ohms, coils etc. I test on the fly and learn from that. Of course, I calculate basic stuff, length etc. but not in a advanced level. I listen to others a lot, then test there experience and tip and go from there as well.

Many say that there is two antennas in this category, the “end fed” and a “random length” antenna, but in this article, there is only one antenna.

Also, many say that the long wire is a “bad” antenna, it’s a compromise, it’s interferes more etc. The G5RV is better, or an dipole etc. and... I can’t agree!

Yes.. the long wire is a compromise antenna, but you can get a really god results if you put some effort in it.

I am using dipoles in the field (as well the long wire) and it’s a good antenna! The G5RV, I can’t say that i have a good experience with this antenna. Yes, they work, but there is better alternatives. DH4, same there. etc.

When I first started with the long wire antenna, I didn't get it. I had a lot problems and the performance was bad. That’s may be a reason that many say that the long wire is a bad antenna!

In my antennas I go from this:

- I use a tuner (you don’t need this if you have the right length)
- I use a 1:1 choke
- I use counterpoise
- I use a 9:1 UnUn

I have heard that you should’t use a 9:1 unun on 160m since a high impedance and ha high SWR. And that probably right... You don’t get a good SWR on 160 without a tuner. Other bands, you can get a OK SWR on the most bands without a tuner and use your radio, but i recommend a good tuner regardless. In my opinion, the UnUn is the most important component of the whole system with the cable length. I will comeback to the UnUn later.


If you have a cheap 971 MFJ tuner, well... then you got some problems! They work, but you have to adjust more etc. I don’t like MFJ tuners, except for the 945E! This is an unbelievable good tuner... if you read my thoughts here: MFJ-945E vs MFJ-971 and MFJ-945E vs MFJ-945E.

So a good UnUn and a good tuner is important!
That is a rule! Don’t be cheap there!


The length of the wire



Is the length of the wire critical? Yes and No. You can take a wire just like that. But you can also follow some rules... and there is a bunch of good pages online there you can read about this antenna, so I will not make another one.

This map is from VKYSF.com there you easy can see the length of the wire that will match the bands. As you can see, a 21 meter long antenna is pretty good! As well a 43 meter long antenna.

So go for a 21 meter long antenna or if you have the space, go for a 43 meter long. But! Don’t forget the counterpoise! So it will be about 31,5 meter or 60-65 meter long.


If you want read more technical etc. about this long wire antenna, here are some good sites:

VKYSF.com - Long wire antenna for portable operations.
HA5KDR.hu – Budapest Fővárosi Rádióamatőr Klub
VE3EED - The "Best" Random Wire Antenna Lengths


The 1:1 choke



I always use a 1:1 choke. Not the “ugly choke”, a real one. The simplest 1:1 choke is 12 turn RG-58 on a FT240-64 ferrite. This one work very well on all HF bands. Yes... there is better one, more complicated to build, but this is really good and simple!

Why use a choke?
You don’t want any RFI back in you radio. And you don’t want to use your coax as an antenna! Yes.. many end fed long wire use the coax as a part of the antenna. That’s why they say that you don’t need any counterpose. Don’t use the coax as an antenna please!


In my main set-up at home I use 2 chokes. One at the antenna feed and one at the middle of the cable line (the picture). Why on this point? Well, I have a connector there that I can unplug the antenna in a easy way from the radio when is a bad weather. I can also disconnect it before the cable go into the house.


The counterpoise



And then we come to the counterpoise. You need it!
The length of the counterpoise depends on the antenna wire... or.. no.. but..

In my experience, I normally use the half length of the antenna wire. So if I use a 21 meter long wire, I take a 10.5 meter long counterpoise. about 15-20 meter long if I use a 41 meter long antenna wire. The length of the counterpoise is not critical. Some say that you can use a 4 meter long counterpoise down to the 40M band, but I don’t know.


In my main set-up I use a HyEndFed 8 band 400W antenna with 2 counterpoises (beside my home made). One 20 meter long (the right cable in the picture) and one 8 meter long (the down-left). The top wire is the antenna and you can see my first choke and the antenna cable feed. I have grounded the pole to the counterpoise screw. The pole have a good ground connection to the earth, you need this for better performance.


You need to put the antenna in a straight line!



No you don’t!
Many say that’s is really important. And yeah... I don’t say that they are wrong, but in my experience... it’s not critical! I have really.. and I mean it.. I have really abused many of my setups... and they worked really good! Sure... they probably should worked a little better if everything was 100% perfect.. But seriously.. how many can setup the antennas perfectly? I can’t in most case.

And yes.. in my main set-up I tried to put it in an straight line, and yes.. it’s pretty straight, but is not totally in a horizontal position. It start’s 4 meters up (the pole above), go to a 10 meter pole (the picture on top) and go to a 8 meter long pole, and then down 2 meter. My plan is to make some changes with the antenna in the spring of 2019. This will be updated then.

So if you can, put it straight of course, but don’t be angry if you can’t.


You can throw up a 20 meter long wire on a tree (or pole), 5-6 meter up and the drag down the rest of the wire to the ground again, like an inverted-v or just trie have the end of the wire in the tree or pole. Put the counterpoise on the ground, under the antenna wire or in the other direction, and the you can hit stations around Europe 1500 km away with no problem on 40-20M (or other bands).

If you want DX, then you need a little better installation and put some effort in it (like mine). And yeah.. some say that you can’t DX, or do it very badly with a log wire, use a mono band dipole instead or a yagi. Well.. with my installation, I always hit DX in my tests.


This map is a normal WSPR for me with 4 small transmitting times. Nothing edit or so.

You see that I can hit many countries with this antenna. And yes.. you can't compare this with a huge yagi with 1500W. This is a small wire on some poles with 5W.

“Fast” and easy set-up that is pretty stealthy as well!
So yes! You can have a good long wire antenna.


The 9:1 UnUn and the tuner



The UnUn is the most critical part in the whole installation. Yes it is! Don’t buy the cheap one and think that you are good for a go. If you make one.. do another one, and one more.. and one more.

If you want to make one, look at Peter's video on TRX Bench on YouTube. Part 4 is about the 9:1 UnUn, but do yourself a favour, look at every one from the begining.. This is the choke and UnUn to go for.




If you want to buy one, look at the HyEndFed, they is one of the best on the market! Seriously!
They have both UnUns and whole antennas, and the antennas is hand make and really good build. This is not crap! If you buy one, you will love it!

I will make a article of mine later.


The bad things..



Is there any bad things?
Well.. you need a tuner, even if you can have a OK SWR on many bands, you want a good tuner.

Here is my SWR without a tuner (with 100w):

160m == More than 3
80m == Between 1.1 - 2.9
40m == Between 1.1 - 1.5
30m == 1.8
20m == 1.2 - 1.3
17m == 2.2
15m == 1.5
12m == 1.6
10m == Between 1.5 - 2.8

You can have a better SWR than this if you put the antenna exactly right and 100% perfect. But again.. how many can do that? So you need a tuner. If you have an internal tuner in your radio, you may use that one (probably not on 160m).

Do you need good ground (not counterpoise)?
Yes and no. If you can have a good earth ground, use it! Bu if you can’t, make some good counterpoise instead and play with them. With some good earth ground you will have some less noise.

Lightning!
I can’t speak about this because I don’t know! I have no experience here. But, a good ground of the antenna is probably the way to go. I have my antenna grounded at home, and in the field, I never ground it.

It can interfere more than other.
In my experience, I haven't notes this. If you put a dipole on the same spot, that interfere as well. And if you interfere, you are to close or something else. Do you get more interfere in RX with this antenna? Not with my antenna at my location any way. The G4RV had much more ground noice and worse signals than the long wire.



Why did I choose the long wire to all the other one?



First of.. all this big mast yagi antenna with huge power.. that’s is a no go right now. Maybe in the future.

Is’t about stealth?
No, I don’t care if you can see the antenna or not, but of course, the smaller antenna, the better for the neighbors. But if you need a stealth antenna, a long wire is the way to go.

The only thing that I chose the long wire was because it was better in all tests of the other antennas i tested on in this location. And I did many test in a bout 6 month before I did a real installation.


Here is my home made antenna, sitting side of the HyEndFed antenna.


So... is the long wire something for you?
It’s depend on your location, what antenna you can put up, your budget etc.

I can just say, give the long wire some attempts (with a good UnUn!!) and see. But give it some time, test different UnUns, put the wires on other points (test even strange set-ups!) etc. Do not think you'll get good results right away..