Hank, "Self-Supporting Towers - Allowable Antenna Areas (Sq. Ft.) Drawing A871266RI dated 9/24/1987 and found in the Rohn Commercial Products Catalog (mine is copyright 1993). For 70 MPH w/no ice the
Roger, Are the "radials" (counterpoise) connected to your tower? You will find that one MUST isolate the radials/counterpoise from the tower and use a good balun to decouple the feedline from the rad
The height is a compromise between ground induced losses on the lower bands and elevation issues on the higher bands. With an elevated vertical (ground plane) mounted 1/4 wave above ground the peak
Tony, Not likely ... with the control wires taped tightly to the boom, the RF voltage induced in the control wires will be very close to that in the boom. The differential will be small enough so as
I strongly disagree. L.B. bases his recommendation for the 88' dipole on only one factor, the ability to maintain a broadside lobe between 3.5 and 14.5 MHz. That's not the only thing to consider. 1)
I would be more inclined to suspect a problem with the beta insulators and/or the driven element insulator. Although they are common to all three bands, the RF voltages are very different at those po
Has anyone made, or know of an easy way to make a template for drilling Rohn 25 mounting holes? I have one section of Rohn 25 that has a bend in the bottom 6 to 8" of one leg ... the tower came over
SSI database lists George L De Grenier of Pittsfield, MA DOB 02 Jan 1917 as SK 03 Mar 2002 73, ... Joe, K4IK _______________________________________________ See: http://www.mscomputer.com for "Self
The SteppIR gain figures are confirmed by both YO and EZNEC. They represent achievable gains with a 22 Ohm feed impedance for four elements on a 32 foot boom and (relatively) narrow bandwidth. Feel f
I've pitched this idea to Mike Mertel several times ... the problem is the change in impedance between the rotary dipole mode (40/30) and yagi mode (20/17/15/12/10/6). It would be necessary to switch
I would not rule it out ... but understand the magnitude of the task you propose. A single feedline antenna that works from 6.9 - 30 plus 50 - 54 MHz in a relatively small form factor (not significan
Interesting to contemplate ... more difficult mechanically and more expensive than a relay to switch the matching transformer which SteppIR have rejected because of concerns with reliability. 73, ...
What boom length is "compromised?" All of the yagi studies show a regular increase in gain with increasing with boom length. As long as there are enough elements to "fill" the boom and the elements
The key is in what you mean by "performs as well." If the only concern is gain at a specific frequency, then the four element antenna will perform just as well as a five, six or more element antenna
If you are going to do a comparison, do a fair comparison. The three element SteppIR with optional fixed six meter element, which is what is modeled in the performance comparison is $1273. To your C3
The C3/C3E has an 18' boom and 7/8 elements respectively. The SteppIR has a 16' boom and only three elements. The two are visually similar ... the SteppIR may even have a lower visual profile. There
While the C3 may be a set of two element antennas located on a common boom, its turning radius and boom length are larger than the three element SteppIR. When looking at an antenna, I look at perform
That antenna is now up and running ... the full story can be found by going to www.ky6la.com/#THE%20MonstIR%20PROJECT Final assembly pictures are: http://www.ky6la.com/finalmonstIR/index.htm 73, ...
20 years ago or so DEO (the QSK-1500) had a receiver front-end protector that was a Chicago Miniature #12 lamp in the receive line followed by a back to back pair of either two or three 1N4148 diode
Most likely a Cushcraft A4S with A744 40 meter add-on to the driven element. 73, ... Joe, K4IK _______________________________________________ See: http://www.mscomputer.com for "Self Supporting Tow