Jim Lux wrote:
> I haven't thought about it at great length, but I wonder if you could
> come up with a simple passive network that could be put at the base
> of a several meter long whip (or loop) with the transformer that
> would provide enough selectivity to restrict you to just a ham
> band. It might be that a single low Q LC might do it? (500 kHz BW at
> 3.5 MHz is a Q of 7), but it might be a couple sections... You need
> to suppress things like BCB only a few bandwidths away (and broadband
> power line noise)
> Jim, W6RMK
>
That is easy to do, but then you have to worry about coordinating
tuning of multiple elements in an array. Any mistuning will
cause phase shifts and throw off the array phasing. Also, the
antenna gain will be a function of component Q. I prefer to
avoid this and just use a low noise 50 ohm amplifier after
the transformer and BCB-reject filter if any.
Rick N6RK
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