[Elecraft] ATU vs. External Tuner

[Phil & Debbie Salas]

"I have a k3 with internal antenna tuner connected to a 40 meter dipole
in the attic. Will the internal ATU work for me visiting other bands
or would I be better off installing a tuner between the rig and the
antenna? Is an auto tuner more preferred than automatic?"

An auto-tuner IS automatic!  The K3 internal auto-tuner tunes a wide range 
and it works great.  But if you are using a coax feed with the 40-meter 
dipole the SWR will be so high on bands other than 40 and 15 meters that 
you'll probably suffer pretty bad coax cable feedline losses.  You might try 
a fan-dipole arrangement in the attic.  As an example, parallel the 40-meter 
wires with 20-meter wires fed at the same point.

Phil - AD5X