>W7LR wrote: Series 9.6 uH from resistive input, then 44 pf shunt across output.
>W5UN sent me to
>http://home.sandiego.edu/~ekim/e194rfs01/jwmatcher/matcher2.html
>which for a low-pass L setup gave me identical values to W7LR using the ON4UN
>package.
>N6IZ wrote: If you have the room full length grounds can get you very close
>to 1:1 Of course you could also drop in a small inductance to tune out the
>-j115 complex load Z.
>N6WG wrote: Assuming it isn't too much (power), you could wind a simple
>matching toroid transformer.
>You need a turns ratio of "sqr rt (75/50)" which is 1.22. This can be worked
>out as 10 turns to the 50 ohm side
>and 12 turns to the 75 ohm side. Then any minor swrremaining can be adjusted
>out at the rig.
Thanks for the tips everyone. I decided to fly the balloon and measure the
impedance. 52 - j92. Not too far off from the modelled value.
I went ahead and added some more wire to the ends of my radials to get to 132
feet. Tough to do through the trees and branches and trespassing onto the
neighbors across a road, but I ended up with 53 + j21. I shortened the
vertical radiator a little at a time and got down to 52 +j10. Pretty good, but
had to quit experimenting when the balloon popped. I think I'll build up the
L-network and 1.5:1 balun ideas and try those too since I can't leave the full
length radials up. Perhaps I'll try to bend the radials to avoid private
property.
Steve KK7UV
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