[AMPS] The Worldwide, No Holds Barred, SWR Quiz.

[Gilmer, Mike]

On Tuesday, October 05, 1999 4:09 AM, measures [SMTP:measures@vcnet.com]
wrote:
> >
> >On Tuesday, October 05, 1999 1:53 AM, measures
[SMTP:measures@vcnet.com]
> >wrote:
> >> >
> >> >Since I'm wearing egg anyway, more can't hurt.
> >> >
> >> >1.  Smith Chart says 1/2 wave cable brings you all the around back
to
> >> >the original load impedance (50 ohms, here).  Therefore the black
box of
> >> >the cable/load looks like 50 ohms, so, all should be happy.  I say
the
> >> >VSWR is 93/50 = 1.86:1 - this caused by the mismatch at the load
end.
> >> 
> >> ?  You have 50 +/- j0 ohms at the position of the SWR meter, and it
reads 
> >> 1.86:1?  I don't see how, Mike.  
> >> 
> >
> >Rich, this says that as long as I have a multiple-half-wave of cable,
> >the impedance of the cable plays no part in the SWR.  
> 
> ok
> 
> >If this were true, what happens to the standing waves that are
created
> >at the load end ( 93 ohm cable, 50 ohm load )?
> 
> >Why would connecting an SWR meter to the near end eliminate them?
> 
>   It eliminates reflections only at the halfwave point.  
> >

It doesn't eliminate the standing waves along the cable.
The reflections from the mismatched load/cable are still on the cable.
What happened to them?
Your contention seems to be that they magically go away when you attach
the swr meter.

If the SWR on the cable is 1:1 (as you say you will measure with your
SWR meter) then there cannot be any standing waves.  Again, where did
they go?

> Cheers, Mike
> 
> >

Ciao, Rich.

Mike




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