30-40m Dipole Kit
The 40m - 30m dipole is simply a driven element that functions as a dipole from 6.8 MHz to
13.8 MHz and as the driven element for the yagi array from 13.8 MHz to 54 MHz. It has no effect on the performance of the yagi. The yagi works the same with or without this option. A dipole for 40m would normally be about 64 feet long but SteppIR have shortened it to 39 feet by looping the element tip back towards the boom. This is a form of linear loading and is very efficient, however, nothing comes for free and with this dipole you will lose about .37 db on40m over a full size dipole. This is hardly measurable at the receiving station end so it is a very reasonable trade off. On 30m since the copper tape barely turns the corner back toward the boom it essentially performs like a full sized dipole. On 40m folding the element back nearly double (the tape comes within about 3.5 feet of the boom on each side) very makes the impedance 25 ohms, a 1.0:1 match for the SteppIR yagiBalun/Unun. |
My personal experience with this Dipole kit I'm glad to say is very positive. Up until its installation my only 40m antennas had been inverted Vee's, and various loops. The Kit has allowed me to become really active, compeditive and heard on 40m, the band has come alive with a very small footprint. Its flat top, bi directional, rotatable and at a reasonable height. The intstall at my qth took about half a day to complete. The brief slide show above outlines the process.
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