Topband: Re: Coax capacitor losses

[Richard (Rick) Karlquist (N6RK)]

You cannot calculate "loss resistance" using only 
a Smith chart, and the dB/ft loss specs.  Instead
of just dB/ft, you need to know conductor resistance
per foot and dielectric conductance per foot.

Rick N6RK



> John Kaufmann said:
> 
 based on its length 
> and its loss
> > specs (dB/ft or dB/m).  Then you can determine whether or not you will
> 
> Rick Karlquist said:
> 
> > You also need to know how much of the loss is due to dielectric loss
> > tangent vs conductor resistance.  For a matched 50 ohm line at 1.8 MHz,
> > the dielectric loss is negligible.  However, it may be significant in a
> > capacitor made out of coax.
> 
> 
> 
> When I refer to "loss resistance" in my earlier post, I am really 
> You can use a Smith Chart to calculate it based on
> transmission line behavior of the line as my earlier post also indicates.
> 
> 73, John W1FV
> 
>