> Working on the assumption that you can get satisfactory reception in th=
e
> upper floors of your property, I would make a quarter wave whip with fo=
ur
> radial wires for a ground plane on each end of the coax. With the far e=
nd
up
> on the roof (maybe, or in the attic to keep it out of the weather) and =
the
> other end hanging from the ceiling in the basement I suspect you will g=
et
> sufficient signal strength.
>
> If you are using 50 ohm coax try a 5/8 wavelength whip and radials as t=
his
> is closer to 50 ohm, although with some reactive impedance.

You can also bend the "ground" radials down to about a 120=B0 angle with
respect to the radiator.  This should increase impedance to approximately=
 50
ohms.  It's kinda like folding/unfolding a dipole.  Approx. 35 ohm impeda=
nce
at 90=B0 relationship (1/4 wave groundplane) and approx 75 ohm impedance =
at
180=B0 angle (dipole).

> I would not worry about trying to deal with matching networks unless yo=
u
are
> looking for every last dB of signal transfer, and from your description=
 of
> the problem it sounds like you just need to get above marginal signal
> levels.

IMHO, the loss due to any mis-match is outweighed by the loss due to the
coax itself.  At these frequencies, that coax will soak up signal strengt=
h
like a sponge.  BTW, the resonant length of the radiator will be 10-30%
shorter than a "calculated" length.  IOW, the formulas will always give y=
ou
an antenna that is "cut" too long.  I guess that's better than the
alternative, though.  ;-)

michael brown (sticking my neck out)

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