Topband: Re: Coax capacitor losses

[Tom Rauch]

> Just use the dB/m loss on the frequency of interest the
actual length of the
> coaxial stub ?
> Or, is this too much simplified....

You cannot accurately use dB loss from wire tables when the
transmission line is very short in terms of wavelength and
especially when the line is used as a capacitor.

First, the SWR is almost infinite. It is an open-ended line
with no termination at all!

Second, the loss is not evenly distributed between
dielectric and conductor losses. Cable loss tables only
accurately apply to lines that are reasonably long compared
to 1/4 wavelength, unless the line is terminated in it's
surge impedance.

73 Tom