Inching Closer to a QSO with the EFHW Antenna

I took out the EFHW antenna matchbox this afternoon with the intent of trimming a length of #22 gauge insulated speaker wire for 20m. I setup a little over 10m of wire with a 1m counterpoise. This was stretched out across the yard and supported by some shrubby about 4 to 5 feet off the ground. The match box was about 3 feet off the ground attached to the Mini60 antenna analyzer through a very short length of coax patch cable. The Matchbox was set at the resonance point found earlier for 20m. Initial SWR was over 3.5 at 14.1Mhz. Sweeping the frequency downwards I could clearly see the SWR improving until the reactance got to Zero and SWR was indicating just over 1:1. The wire was resonating but at a frequency much lower than I needed indicating the wire was long. I set the analyzer to 14.2Mhz and started trimming the end of the wire bit by bit until the SWR dropped to around 1.8 or so. I ran a sweep and found that the minimum SWR was right at 14Mhz while 14.35 Mhz was well above 2:1. The bandwidth was measured at 455kHz so I set the analyzer to 14.35 Mhz and trimmed until the SWR dropped to about 1.8. Here is what the SWR plot looks like finally:

2016-08-05_17-50-50

I have purposefully left it a bit long as I intend to run this as a vertical and am not sure what the effect on matching will be in its final position and with feed-line attached. I just charged up the FT-817ND and hopefully I’ll be able to take this outdoors tomorrow for a test.

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