The W1SFR Endfed antenna is up and things went very straight forward with the install. My options for a location a limited so I ended up having to place the antenna in a tree that besides our mini home and then down to the shed about 40 feet or so away. The antenna runs parallel with the mini home along the north side of the mini home. The feed end of the antenna is about 25 feet up and mounted to the tree. The far end at the shed the antenna is about 15 feet from the ground. The coax from the antenna to the shack is about 65 feet in total as the Endfed antenna uses the coax as the counterpoise and Steve W1SRF recommends you have at least 25 feet of coax. The time came to flip the switch on my antenna analyzer and see some SWR results:
Band. Freq. SWR
40. 7.0001. 1.9
40. 7.070 2.5
30. 10.100. 4.4
30. 10.150. 4.5
20. 14.001. 4.5
20. 14.070. 4.3
17. 18.068. 1.5
17. 18.168 1.5
21. 21.001. 1.8
21. 21.070. 1.8
I was a bit alarmed by the results so I emailed Steve W1SFR regarding the results from his Endfed antenna. He came back with positive comments saying my results looked very normal. This is the very reason it's said that with the Endfed antennas you need to use a tuner. The next step was to connect the Icom 7610 to the whole mix and see how things worked. This is where Murphy popped his head up to give me grief! I began to transmit on 40 meters and with the power, at 40 watts things started to happen around the shack and house! In the shack my PC was not running but the monitor was in sleep mode. All of a sudden the monitor would wake up from its sleep, on my PC desktop I have a program that allows me to post notes on the desktop when I transmitted CW I would see random letters being typed on a posted notes on the desktop, my electronic keyer would send dah's and no dits and finally our new electronic washing machine would just shut down. The other band I tried was 20m and when transmitting CW at about 60 watts the PC monitor would wake up from its sleep but no other issues. I was wondering it was the RF coming back on the coax or because the Endfed run parallel with the mini home is about 15 feet away from the home?
I contacted Steve again who informed me that it could be RF on the coax as it's a counterpoise. His suggestion was for me to purchase a 1:1 balun and from there see if it solves the issues. Steve suggested it may or may not solve all the issues and I may have to look at other options for unsolved issues. Well, I have a decision to make....do I want to start spending more money and go down a road that may lead me to gain more "stuff" but still not being able to use the antenna. Now I did get some comments from my blog readers who do have and are using with success an Endfed antenna.
11 comments:
Mike, the endfed may not be the best antenna ever but if well made a antenna tuner should not be needed. At least not for the center part of the bands it is made for. I got a 3 band endfed which is 1:1 at center of 40m, 20, and 10m. Have been using it portable with 50W without any problems. However since the coax is used as counterpoise RFI problems are easily created. I would recommend a 1:1 balun as well both at the feedpoint as directly behind the radio. There are some other things you could do like connecting a wire counterpoise at the earth screw of your radio. Another thing comes to mind when viewing your SWR....since your antenna runs parallel to the house...does the house have something in it that radiates like zinc raingutters or alu strips? This could seriously change the SWR. Sorry to say but a SWR of 4,5 might be tuned by your tuner in the radio but still at the antenna it is wrong and creates a lot of loss (coax!). A SWR below 2 is acceptable. At least the SWR on 17m is good and it seems propagation is good these days on that band at daylight. Good luck, 73, Bas
Been there. Does the W1SFR balun have a counterpoise connection? I had rf in the shack issues until I installed a 20' wire counterpoise (just laid on the ground). Without that wire the coax shield is the counterpoise.
Alternately you could add a 1:1 isolation balun before the coax enters the house but you need 20' of coax before the 1:1 balun. See Balun Designs Model 1115.
There is a good thread about end feds and grounds on Facebook > Stealth Antennas at the moment.
Good Luck and congrats on the move.
73,
Paul VA3ZC
Hi Mike - one thing you might try before buying a balun is to use a different length of coax coming into your shack from the antenna. If you have it on hand, try to jumper in an additional 10 feet or so and see if it makes a difference.
73 - John AE5X
Good evening Paul and greetings from New Brunswick, the W1SFR balun does not have a counterpoise connection. The design of the Endfed is that it uses the coax as the counterpoise. With regards to having 20 feet of coax before the house I have about 45 feet of coax before it enters the house so I am good there. Thanks for the facebook info during the weekend I will check that out.
Have a good Friday and weekend Paul and again thanks for the info.
73,
Mike
VE9KK
Good evening john again very nice to hear from you, it's funny just before I read your comment I came up with the same idea! I tried 10 feet, 15 feet and 20 and it was all the same. But it was worth a shot but after the tests I placed an order for the Balun Designs 1115 balun. So when that comes in we shall see how things turn out.
73,
Mike
VE9KK
Good evening MJ and thanks for the info, I will be doing some tests over the weekend to see just what power limit I have before things start to happen. I have ordered the 1115 Balun from Balun designs and it should be here within the week. It is a nice quality 1:1 balun and I will see what difference that makes.
Thank very much for the link and the info.
73,
Mike
VE9KK
Bas as always it's great to hear from you, this Endfed indicate online that it's good for 6m to 40m so it's really not a 3 band Endfed. On the weekend I am going to run some tests to see at what power level I have issues. As for the 1:1 balun I have ordered a good quality balun from Balun Designs (1115). As for the antenna running parallel to the mini home we have plastic gutters and plastic siding so there is no metal or zinc. I have some ideas that I am going to try on the weekend and will be posting in the blog the results.
Bas thank very much for your time and the info.
73,
Mike
VE9KK
The EARCHI endfed (google it - I think it is the same as W1SFR's) does have a counterpoise connection though they say you don't need to use it since the coax is the counterpoise. However you can use it if the coax counterpoise is causing problems like rf in the shack.
I was operating portable in Antigua with the EARCHI and getting rf on the TV. I bought about 20 ft. of wire and attached it to the counterpoise connector and voila, no more rf in the shack. Plus the antenna worked better.
Try taping some wire to the shield of the pl-259 connector at the 9:1 balun. That is the same as the counterpoise connector. That should do the trick.
Then get on the air and make some contacts.
Good luck and good DX from VE3 land.
Paul VA3ZC
Good morning Paul very nice to hear from you, I did Google the EARCHI and I do see an extra wing nut on the unit for a counterpoise. With the W1SFR there is only one wing nut and that is for the antenna. Looks like I am going to have to attach a counterpoise wire to the outside of the PL257 connector configuration.
Thanks for the info and I will be looking into that today.
73,
Mike
VE9KK
Mike, glad you are back on the air. if you have some space just run a simple dipole or vertical wire for 20 or 40. EF are nice especially for /p use but a nightmare to tune.
Stefano
Good evening Stefano very nice to hear from you, the vertical or any other antenna will have to wait until the spring time. This antenna is meant to get me through the winter. At this point in time I have lots to do around the new place so the idea of an antenna is one of get the easiest one up and live with it over the winter.
73 and great to hear from you Stefano,
Mike
VE9KK
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