At 07:54 AM 2004-06-04, Bob Taylor K8FI wrote: Can anyone come up with more information on this? http://www.uri.edu/news/release/?id=2659 Bob, I'm skeptical of his claimed 80% to 100% efficiency if h
At 10:00 AM 2004-06-11, Jerry Keller wrote: I may be one of those Pete calls "those with trees conveniently situated", and I am indeed "tempted" by this idea for a short vertical for 160M...:-)... ha
Kintronic also has a link to a more theoretical IEEE article on this antenna: http://www.star-h.com/publications/ieee2002.pdf In the end, this is just a permutation of a short fat vertical with a lar
At 08:26 PM 2004-06-21, RICHARD BOYD wrote: And, it shouldn't take much more wire. Let's say the stakes are one or two or three feet apart at the perimeter, you would have, say, a 130' radial and a t
At 09:53 AM 2004-07-20, Bill VanAlstyne wrote: I couldn't help but wonder at this snippet from an AP newswire article in this morning's paper regarding how the Santa Clarita wildfire in California su
At 08:17 AM 2004-08-04, Joe Giacobello wrote: I recollect that several months ago there were several posts referring to the availability of 500 ft. rolls of #14 wire from Home Depot (Lowes?). I was a
At 05:59 PM 2004-09-09, you wrote: Using EZNEC 2.0, I model a one-wavelength wire at 50 feet above real ground ("normal"), and feed it at 50% from one end. I get a pattern that has nulls off the ends
At 08:57 PM 2004-10-01, David Kozinn wrote: As another point of reference, the Lowes nearest me (in Rockland County, NY, very close to the Bergen County, NJ border) sells the same thing for $20 (stra
At 07:48 PM 2004-10-01, Jim Miller WB5OXQ wrote: I wonder how a vertical would perform on top of my office building? Sheet metal roof. 20' high at center, 18' at eves. 160'X80' dimensions. I have a t
At 11:36 AM 2004-10-02, "Jim Miller WB5OXQ" <wb5oxq@grandecom.net> wrote: There is nothing electrical on the roof. the AC units are on the ground. Sounds good. There is this 190' tower beside the bui
What about the MonstIR? Too big? Too expensive? http://www.steppir.com/pdf/monstir%20brochure.pdf 73 Terry _______________________________________________ See: http://www.mscomputer.com for "Self Sup
If you look closely at these N0KHQ-type antennas, you will see that they are center-loaded by the inductance of two shorted sections of transmission line. I visualize it this way: The current on each
Tom, Do you have any reference on the USIA array? The only hit I got on Google was your message. Keep clam, Terry N6RY _______________________________________________ See: http://www.mscomputer.com f
I'm sure Tim meant to say that the impedance will go up with sloped radials. I modeled quarter-wavelength verticals on a 50 foot tower, with four 45 degree sloping radials. The feed impedance at reso
On Sun Jun 12 09:49:54 EDT 2005, Jim Jarvis wrote: I differ on the topic of radiation pattern. Not sure about the source of Tim's caution, but if we're talking about 2 resonant radials...it's just a
According to modeling in EZNEC, as long as the two radials are symmetrical (180 degrees apart, same slope), the azimuth and elevation patterns are very uniform, and the horizontal radiation cancels q
Excellent points, gentlemen. Even with a current balun/choke at the feedpoint, the coax feedline can easily couple to the antenna & radials and skew the pattern. I've included approximations of my tw
Just for fun, I put your antenna and feeder into EZNEC+ over average ground. Here's a look: At Antenna == Bare #12 conductor F=3.809 R=72.8 SWR(50 ohm)=1.46 or L=472.3/F Looking into 100' of 75 ohm,
That's fine if the load is matched to the line Z, or for 90 or 180 degree lines, but the phase shift will not be 135 degrees if the line is mismatched, which is often the case with verticals in a ph
Using a folded monopole will indeed raise the feedpoint impedance (by a factor of 4, which can make matching easier), but the radiation resistance and ground losses are unchanged, since the net curre