[Lowfer] To Q or not to Q?

[Ed Phillips]

Bob Roehrig wrote:
> 
> On Wed, 13 Feb 2002, Ashlock,William wrote:
> 
> > Do you guys know what the effect is on your signal when you go from a plain
> > old garden pea variety coil with a Q of say...200 to an exotic coil with a Q
> > of 400?
> 
> Excellent question. There must be a point where a bit more Q is not going
> to show up in the final result.
> 
>                     73        Bob Roehrig        K9EUI

	That's fairly easy.  When the equivalent series resistance of the
loading coil (the reactance divided by the coil Q) gets to be less than
say 10% of the ground resistance nothing will be observable, and if
equals the ground resistance the signal will only be down by 3 dB.  I
love big coils and high Q, but don't place unreasonable expectations on
their use.

Ed