Topband: NCC and phased Active verticals follow up

Rick Karlquist richard at karlquist.com
Wed Oct 24 16:41:30 EDT 2007


Lee K7TJR wrote:
. Does any one know if DXE
> publishe
>  s amplitude and phase shift specs for their Hi-Z antenna/amplifier.
>
> Lee K7TJR Oregon  www.k7tjr.com

They don't publish anything on that.

The LC tanks that are selected with jumpers appear to be constructed
of ordinary parts with 10% or 20% tolerance.  The effect of
those could be modeled w.r.t. amplitude and phase shift.
I suspect this is the main source of any amplitude and phase shifts.
I can't remember if the FET amplifier has negative feedback.
If not, its gain would vary with FET transconductance, which is
poorly controlled in most cases.

Rick N6RK



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