On Monday, October 04, 1999 4:23 PM, Jon Ogden [SMTP:jono@enteract.com]
wrote:
>
> Vic Rosenthal wrote:
>
> >> ? You have 50 +/- j0 ohms at the position of the SWR meter, and it
reads
> >> 1.86:1? I don't see how, Mike.
> >
> >Because an SWR meter computes SWR by comparing forward and reflected
> >power, not
> >by being an impedance bridge!
>
> But Vic,
>
> Source impedance is 50 Ohms. Load impedance is 50 Ohms. The
transmission line is a length where even you agree that the transformed
impedance at the end of it is 50 Ohms. So where is the impedance
mismatch?????????
>
At the load end. 93 ohms to 50 ohms. Seems clear to me!!!!!!!!!
1. Does the length of the coax effect this ratio of Zload to Zcable?
2. Isn't the fact that Zload not equal Zcable what creates the standing
waves on the cable?
If answer to one is : No
AND
the answer to two is: Yes
Then:
Where do the standing waves go when you add a SWR bridge to measure it
all?
- It's not Heisenberg's uncertainty principle :)
Are Rich and Jon saying that the mismatch of the 50 ohm SWR bridge to
the 93 ohm cable (at the near end) create standing waves that cancel the
original ones (created at the far end) and yield a 1:1 condition?
Mike N2MG
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