A number of years ago, the SWR on my shunt fed tower kept getting wider and flatter. The feedline buried hardline with an aluminum jacket. The soil here in upstate NY had eaten away the aluminum and produced a goo. When I disconnected all the feedlines to the tower the shield on the 160M feed showed a high resistance. The shield of the other feedlines were providing the return path. So, nice SWR but not a very efficient antenna. 73, N2TK, Tony
-----Original Message----- From: [email protected] <[email protected]> On Behalf Of Don Wilhelm Sent: Monday, December 03, 2018 10:07 AM To: [email protected]; [email protected] Subject: Re: [Elecraft] Flumoxed Not necessarily - notice the relatively flat SWR (less than 2:1) over a large frequency range (for 160 meters). That normally means that the antenna is acting more like a resistance than a radiator. I would expect the SWR on 160 meters to be low only over a 25kHz or at most 50kHz range of the band. When the SWR bandwidth of an antenna increases, you should be looking for a problem in that feedline, antenna to feedline connections or in the case of a vertical, the ground radial system. One possibility is that the radial wires installed were aluminum - they do not last very long in the ground, for some reason, moles like to chew on them. 73, Don W3FPR On 12/3/2018 9:18 AM, Don Roberts via Elecraft wrote: > Lee, it looks like your inverted L wire has stretched. Check with an antenna analyzer and you will probably see your resonate frequency is lower than 1.8 Mhz. Perhaps time to do some triming. ______________________________________________________________ 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] ______________________________________________________________ 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]
