I want to end-feed a half wave vertical so I can get a nice low angle of radiation. The base of the antenna would be about 0.05 to 0.10 wavelengths above ground. It looks like the antenna impedance w
Have you considered a coaxial dipole design? It can be made several ways. The most popular is to fold back the shield 1/4 wave over the outer jacket of the coax leaving 1/4 wave center conductor. The
In reference to an auto transformer matching network for a half wave vertical: In John Devoldere's book, Low-Band DXing, he describes a balun intended for this purpose. It was designed by W1FC, and i
...net net....if you want to lower your primary radiation angle going to 1/2 wave vertical isn't going to get you there. The work effort has to be spent on the radial system but in reality if you are
I can't think of a more difficult thing to do *properly* than to end feed a half wave. There are a good may half-baked feed systems around, but the only reliable and simple system is a resonant tunin
I agree with Tom's assessment of feeding a half wave antenna. After thinking about using a transformer, there is one parameter which is really difficult to overcome, stray capacitance between primary
Is there a particular reason why one would want a broadband transformer here? A dipole is going to be a fairly narrow band device, so why not use a narrow band matching network of some sort. Also, wh
Jim was asking about feeding an unbalanced antenna (vertical), not a dipole, however your idea still applies. Actually, an air core transformer would work (almost). Taking this thought and evolving t
I doubt that a 9:1 transformer is going to do the job... The impedence at the end of the half wave is several thousands of ohms and is highly reactive - plus lthe reactance changes rapidly as the fre
Not necessarily on the reactance. And a plain old parallel LC network will match that antenna to 50 ohms exactly. Just tap up from the bottom of the coil while adjusting the capacitor. ( I usually ma
The easiest way to get high quality multiband perforance from half wave verticals is to put up several single band half wave verticals, each with its own tuning network, over the same ground field. U
I have a 30 meter half wave vertical mounted on a dock piling over salt water. I feed it with an old Dentron "Super Tuner" right at the base. The tuner is housed in a Rubbermaid storage box. On long
Unless you want to get the hell shocked out of you, like some dummy you know did with a balloon holding up a full 1/2 wave on 160. ** Why that is positively - or was it negatively - illuminating?? de
First, I want to apologize for taking so long to respond to everyone who put time and thought into helping me with my question posted Jun 1/05. It is very much appreciated. June was pretty much a los
Jim, My feeling is that this is much ado about very little... First, a 4 degree difference in MODELED takeoff angle on 160 is meaningless...The presence of power lines, house wiring, plumbing pipes,
First, a 4 degree difference in MODELED takeoff angle on 160 is meaningless...The presence of power lines, house wiring, plumbing pipes, sewer lines, telephone wires, CATV cable, and on, and on, wit
<snip> Yep, a 3/4 wave antenna is not a low angle radiator. Anything longer than 5/8 wave and the maximum lobe starts to go up. That's the reason you see so many 5/8 wave mobile 2M antennas. You may
I have up end fed 1/2 wave vertical wire antennas. I use .4 wave or longer radials. In my experience, long term A/B comparison to 1/4 wave verticals over the same ground field, and using the same fee
A Most antenna modeling programs do not model the propagation medium (i.e. the atmosphere). And, they make the "flat earth" and "uniform earth" assumption. The pattern data is typically at infinite d