Jim,

Typically, the internal tuner won't match much more than a 3:1 or maybe at 
the outside 6:1 SWR, the older internal tuners on the TS-850 would match 
10:1.  Now, some of that might depend on your reactances, but since they 
have small caps, they don't have the capabilities of external tuners.

Then, let's say you have a couple different scenarios.  First, let's say you 
want to be real efficient and feed your wire antenna with open-wire.  You 
could try running it through a balun, but it would probably be easier to 
have an external tuner with the balanced feed point on it.

The second scenario: you want to run a linear amp.  You'll then definitely 
need an external tuner.


----- Original Message ----- 
From: Jim Gammon
To: [log in to unmask]
Sent: Thursday, July 19, 2012 1:10 PM
Subject: External tuner vs internal tuner?


Steve, what advantage is there to using an external auto tuner
over the internal tuner in the TS-480? I have the 100 w model and
really think it's a great rig.  That question about the tuner has
nagged at me though.  I have been wondering if it would be
worthwhile to get something like an MFJ external tuner, or is
that simply redundant because of the existing internal one.  I
have occasionally used the rig running low power when I had
terrible SWR and still worked stations.  Jim WA6EKS