Here's a more current reference, with good citations: P. R. Winniford, et al., "New Analysis and Design Techniques for Arbitrary Reactance Trap Dipoles," IEEE Open Journal of Antennas and Propagation
A safety point: A good motor cap can hold the instantaneous value of the alternating voltage at the moment of disconnect. It's good to short it before touching the terminals. I use a jumper, and the
I still think of the foreground slope concept as "Moxon Slopes," from the work and publications of Les Moxon, G6XN, who was a great personal inspiration to me. An interesting related question for whi
A couple more re ground and antennas: J. Breakall, "Maximizing Performance of HF Antennas with Irregular Terrain," 2021, https://www.contestuniversity.com/wp-content/uploads/2021/01/Contest-Universit
For a start, see https://web.archive.org/web/20200711193004/https://k7nv.com/notebook/ppinfo/ See also https://ve3vn.blogspot.com/2015/11/choices-on-adapting-prop-pitch-motors.html: "On a bench test
This is a great step, but I find I can't access all of the subfiles at that URL http://www.hamoperator.org/k7nv.com/. However, you can find the whole site at https://web.archive.org/web/2021012914531
Please be sure to use redundant means of supporting the mast and antennas. There was an frightening accident a number of years ago when the bolts on a thrust bearing holding a mast snapped and it fel
Note that the return loss measurement should be made with an open, short or non-dissipative reactive load, not a dummy load. Dave, W6NL/HC8L Loss = 10 Log ((SWR+1)/(SWR-1)) After determining the loss
In designing some Yagis to be built without further adjustment at a DX contest station, I experimented with calculating the shortening of the driven element tip to compensate for balun leads. As a si
You can also download the associated spreadsheets at https://www.dropbox.com/scl/fo/u4o0teln9hkn7hagbs5eu/h?rlkey=fy1rj0kw4vjld2ddjc17m4rza&dl=0 Dave, W6NL/HC8L 73, Mike W4EF..................... On
From "Physical Design of Yagi Antennas," ARRL 1992, pg. 9-2: "This problem is resolved in a short paper by Jaggard [D. Jaggard, "On Bounding the Equivalent Radius," IEEE Trans AP, Vol. AP-28, May 198
Considering it as a conductive sheet, from Jaggard the equivalent radius for a triangular tower shape comes out about 42% of the face width (equivalent diameter is 84%). There are formulas for two pa
I've used both drawn 6061-T6 and 6063-T832, the yield strength and other parameters are essentially the same. The yield strength for both is around 35-40k psi. Many other tempers of 6063 are not as s