[Elecraft] K3 SWR Accuracy - reprise

[Phil & Debbie Salas]

Transmission line theory (and therefore the Smith Chart info) IS correct. 
Transmission line length DOES transform the impedance, but not SWR.  So you 
may be changing the impedance to something that your tuner can tune when you 
add coax length, but you are not changing the SWR by adding coax - other 
than the change due to coax loss which is negligable for short lengths.

Now I do agree that different SWR meters probably read differently when the 
SWR is the same but the impedances presented to the two SWR meters are 
different.

Phil - AD5X

----- Original Message ----- 
From: "Steve Ellington" <n4lq at carolina.rr.com>
To: "Phil & Debbie Salas" <dpsalas at tx.rr.com>; <elecraft at mailman.qth.net>
Sent: Wednesday, November 04, 2009 5:59 PM
Subject: Re: [Elecraft] K3 SWR Accuracy - reprise


> The first statement is correct. Length of coax will transform impedance 
> and cause SWR meters to read differently.
> I've seen this Smith Chart reference before and it makes no sense. You can 
> certainly use your feeder to "match" your antenna. Of course, if SWR 
> meters didn't care what the impedance is then yes, it wouldn't matter 
> where you put it along the line but such is not the case.
> Steve
> N4LQ