A doublet is a half wave -???? ? wave on each leg tuned to the desired frequency. Each ?leg is ?Length (feet) = 468/2 x frequency in Mhz and will be approximately the dipole will be approximately 50 ohms if fed by 50-ohm coax to get an optimum? ?SWR ¨C the G90 can tune up to 1000 ohms in its autotuner.? Multiple bands can be used by feeding a ¡°fan¡± of dipole elements fed by a single coax line.? This is not as critical for receiving only.? An inverted ¡°V¡± is a good choice also essentially a dipole with a feed point elevated and ends coming down in a ¡°V¡±.? This provides a lower angle of radiation for DX.?
?
You will likely get many more responses to this than you need.? Google dipoles.
Sorry to post again on the antennas, but I¡¯m working on the subject, and the more I read about it, the more questions I have.
First of all, I thought the dipole had to have a total length of one wave, but I see a lot of constructions that are actually two-quarters of a wave, which is what we call double-half wave. This is interesting because the thread is shorter.
In addition I just read that a doublet on 7MHZ, also works on 21 MHZ with the third harmonic.
Here again I read that the impedance is more towards 73 ohms, but decreases with the height, so roughly 50ohm of coaxial is good.
So my question remains the same, I anticipated the possibility of 5 wires on each side of my dipole. What are the best lengths to provide (Knowing now that harmonics can play) to optimize the reception of maximum bands.?
