I'm designing a set of 4 pennant antennas for 160. They will be switchable
in-out to a common feedline. I'm basing the design on K6SE's work published
in 7/00 QST.
I've decided on the Point-fed design to allow the use of 4 switched elements
90 degrees apart.
The feedpoint impedance is modeled to be around 960 ohms or so. A simple
transformer can do the trick to get it down to 50 ohms. However, when
pondering about the pre-amp, I'm thinking of looking at doing the
transformation in an active element instead of a transformer. Finding a
high input impedance device for topband should not be a big deal. The
amplifier can then be matched to 50 ohm output.
Is this a reasonable approach? Would it be better to stick with 50 ohms
in/out in the active element? Am I inventing the wheel here?
Ford-N0FP
ford@cmgate.com
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