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This is to receive WX APT signal on 137 Mhz and sometimes to work on VHF or
listen to avi band. According you 'd it be interested or not at all to select a discone instead of the helix ? There is no advantage of using a discone, or even drawbacks vs. the helix, excepted the price ? Thierry "Roy Lewallen" wrote in message ... A discone antenna is a vertically polarized, broad bandwidth antenna. A quadrifilar helix is a circularly polarized, relatively narrow bandwidth antenna. About the only thing they have in common is that both are omnidirectional in azimuth. A quadrifilar helix is a more suitable antenna for receiving the circularly polarized, relatively narrow bandwidth signals from a weather satellite. Roy Lewallen, W7EL Thierry wrote: Hi, To pick up a 137 MHz signal from wx satellite (POES), are the discone and quadrifilar helix antennas similar, I mean, they are different in design but for the rest ? Are they both omnidirectional and are they both able to change automatically the elevation and azimuth to the satellite direction without interruption and without requiring a rotator ? or only the helix provides this capability ? Thanks in advance Thierry, ON4SKY http://www.astrosurf.com/lombry |