On 12/10/2015 4:14 PM, Brian D. Comer wrote:
I think stating any particular antenna configuration is unacceptable is ignoring what could be an ideal antenna for a given situation.
Absolutely! Situations differ dramatically. A low angle radiator on 80 in the evening is likely to underwhelm you if your need is to communicate over 150 miles.
As I understand it a rhombic uses a resistor, and sometimes works quite well.
Ummm ... rhombics *always* work well for their intended use. Unterminated, they are bi-directional. With the terminating resistor, they are unidirectional in the direction from the feedline to the terminator. Since terminated rhombics are usually 2 or more wavelengths on a side, they have very narrow beamwidths with a big F/B ratio, low radiation angle, and high gain.
They were used on point-to-point HF circuits in the 30's through maybe the 60's or so. I worked coastal marine in 56-57. We generally used V-beams with wider beamwidths since our targets were ships that moved around, but we had a couple of rhombics, one aimed at NMO in Hawaii. Tap the key at 5 KW and they told us we were QSA 11R5:-)
OCF's can serve well in the right situations and with the right precautions to mitigate the downsides. The infamous B&W folded dipole was never billed as anything other than what it was ... an antenna with a non-inductive resistance that pretty much swamped any effects from the antenna, and could be used 3 - 30 MHz, in the right situations.
Tom Schiller, N6BT, likes to show his "illuminator", a 300 W light bulb fed through a common mode choke. He even put three up as a "phased array. Any RF in any conductor will radiate.
73, Fred K6DGW - Northern California Contest Club - CU in the Cal QSO Party 1-2 Oct 2016 - www.cqp.org ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
