Finished up building and tuning the 80m 1/4 wave vertical , aka Marconi antenna, today.
Picked up a 1/4 Mile of 14 gauge galvanized fence wire yesterday. I had the bare minimum 4 X 76' radials in place already and cut another 8 X 76' for install today. Cut all 8 lengths in the front yard then took 4 runs at a time up the hill for installation. When all was said and done I had a total of 12 76' radials in place.
Next up was the big test. Cut the vertical element for an SWR null at 3.5 MHZ. After the tuning with 4X76' radials , + ground in place i was getting a very acceptable 1.3 : 1 VSWR. After adding another 8 radials the VSWR at 3.5 MHz changed to a perfect 1:1 VSWR...YIPPIE.
Found that the vertical wire need a bit of strain relief at the base ... was worried that it would eventually break. Did two things, lighten the counter weight and allowed a bit more droop in the horizontal ( vertical ) element. Final task was to silicon the base ... no metal , wires or important bits exposed to the weather! Will take some pictures and post at some point.
Final check ... 3.5 MHz VSWR 1:1...still perfect.
Last night after work 05:00 gmt I worked 2 stations one in France and another in Czechoslovakia both gave me a 569 signal report and that was with 4 radials. Look forward to giving the antenna a go tonight after dark.
Next up .... 160 Meter Marconi , these antennas rock!
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