Scott, The main 137 antenna will be an inverted-L with two, 392 foot long #10 copper clad horizontal wires fanning out from the tower in a V. I am using this V-Beam antenna for reception on LF now an
Dear J, Elnec shows the radiation resistance of the antenna with all resistances set to zero, to be about 0.02053 Ohms. It seems to be very strange. Simple formula for top loaded vertical R=1600(H/la
Alexander, how much topload on your vertical? Mine is 22m high with 300pF top. R at feedpoint is 24 Ohm. After some tests (compared with DCF39) and calculations the radiating restistance seems to be
Peter, Thanks for catching my mistake... Elnec was correct, but I made a typographical error. The decimal was one place off. It is 0.2053 Ohms, not 0.02053 Ohms, and is close to the 0.16 figure you h
Elnec was correct, but I made a typographical error. The decimal was one place off. It is 0.2053 Ohms, not 0.02053 Ohms, and is close to the 0.16 figure you had for an antenna height of 20 meters. O!
7.6 Ohm of coil resistence is reasonable. But it can be decreased if increase a diameter of a coil. Very aproximative coil Q-factor is about coil diameter in milimeters if step of wireing is optimal
Alex, The antenna is in a flat mountain valley far from any trees, but it has a long low house running from about 7 meters to about 27 meters from the base of the vertical tower. Other buildings and
7.6 Ohm of coil resistence is reasonable. But it can be decreased if increase a diameter of a coil. Very aproximative coil Q-factor is about coil diameter in milimeters if step of wireing is optimal
Alexander, how much topload on your vertical? Mine is 22m high with 300pF top. R at feedpoint is 24 Ohm. After some tests (compared with DCF39) and calculations the radiating restistance seems to be
The antenna is in a flat mountain valley far from any trees, but it has a long low house running from about 7 meters to about 27 meters from the base of the vertical tower. Other buildings and wiring
Certanly may be it is more easy to build more powerful TX not such a complex antenna because You have ERP restriction. All of this can be more interesting fo Russians where there is no ERP restrictio
Dear J. and Alexander, thank you for that most interesting ongoing discussion. In my opinion, the comments and formulas from RA9ME make up an excellent tutorial on LF antenna design in a nutshell. Ve
Alex, Jim, Markus, and LF, The reason for setting my calculations in front of all, is that I am new to LF and want the station to have early success, rather than being a set of mistakes and recoverie
Dear J, Alex, Thank you for your continuing help. I am retired and live on a fixed, small income. Litz (sp?) wire in not being considered. Solid coper wire yelds Q-factor about 1/2 of Q-factor with L
