You need +j34 ohms in parallel with your coax coming in. This is about 3 microhenries. This would be around 6 turns on your coil if the turns are spaced a wire diameter. IOW, tap the coax 6 turns from the grounded end. Then tap the antenna to whatever tunes to 1.83 MHz.
Rick N6RK On 11/1/2017 9:54 AM, MR TREVOR DUNNE wrote:
Hi All I finally got the vertical up and running, problem I have now is I can't find a low SWR on the coil, the best I can get is about 2.8:1 no matter where I tap the coil that's the best SWR, I can move that point up and down the band by moving the tap but the SWR stays the same, My current set up is about 55ft vertical I have 2 loading wires in a T shape, wires are 50ft either side of the vertical and the are pretty level and in line, I have 38 radials averaging about 45-60ft long, I will add more when time allows but don't the make the SWR worse ?? With no coil I get resonance at 2.12mhz with R=16 X=2 on my MFJ269, The coil is 25ft of 5mm copper brake pipe in a 4" diameter, the coil is attached to base of the vertical and the other end is grounded, Any pointers on what I can do to get a better match, Thanks Trevor EI2GLB _________________ Topband Reflector Archives - http://www.contesting.com/_topband
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