John, As a user of an 80M OCF dipole, I knew it was going to be a compromise. My goal was to be able to put up an antenna on a small lot that would get me on the air on 80 and 40. I don't have room to run even a full 1/2 wave dipole for 80m, or a lot of wires, but the OCF dimensions (45'/90') fit in to my lot with a bit of zig-zagging. I don't use the OCF on anything higher than 40m as I have a small beam for the higher bands. Yes, common mode current can be a problem if not designed properly. I use a 4:1 current balun and an additional 10 turn choke at the feed point, in addition to a single point ground system. No issues at this location. I agree simple dipoles or fan dipoles would be desired. In my case, I do not have 66' in both directions, of the direction of interest, to string a full size 80m dipole. But I can get 45' in one direction and the 90' leg does take a turn at 75'. Point is, we put up what we can, understanding the compromises (antenna theory) in the space we have. One point of relative (A/B) comparison I can share . The 80m OFC is resonate of course on 17 and 12 meters. I have a rotatable trap dipole (D3W) on the tower for 12/17/30m at 42'. The OFC is at 35'. When comparing signal strength of the two antennas to EU, which is where the OFC is broad side to on 17m, the OFC is about 20DB less signal strength than the rotatable trap dipole. So yes, the OCF is a compromise. There has been one benefit to the OCF in contesting, and that is in the NAQP and SS contest. With it's height above ground at only 35', it works well for close in state side contacts on 20/40/80. It comes down to what the operators goals are, and understanding antenna theory. 73 Gene N9TF
----- Original Message ----- From: [email protected] To: [email protected] Sent: Thursday, December 10, 2015 7:16:30 AM Subject: Re: [Elecraft] Rick & antennas... How do you know that it works well? Low SWR or even working DX is no indication of antenna performance I really do not understand the popularity of OCF antennas. They can have considerable common mode current making them susceptible to feedline radiation and RF in the shack. Simple dipoles or fan dipole for the desired bands is a much better option. John KK9A Wed Dec 9 18:06:50 EST 2015 Previous message (by thread): [Elecraft] P3 cw waterfall Next message (by thread): [Elecraft] Rick & antennas... The Buckmaster is recommended to be installed as an inverted V. That's sweet that the E Tuner gets along with it but I have the 3,000w version and run full legal limit on all bands (where allowed) that it operates on without the need to use my tuner. Not high performance eh? Funny stuff. I suggest anyone considering this fine antenna consult the eHam reviews of it by people who actually own the antenna & have experience with it. Comparing a beam antenna to a wire is sort of ridiculous IMO for what should be more than obvious reasons. Lotsa haters out there as usual. kd0bcf ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
