remote tuners at the feed point are great. I did that with my statinbefore the lighting strike that took out my auto tuner. I had a remote balunn and tuner mounted  atthe point where the ladder line came to the house down fromthe dipole, and then coax into the shack and to the rig  itwas a relaly nice way to run  
good luck and 73
kb7nla
On Dec 13, 2011, at 6:42 AM, Howard Kaufman wrote:

> I guess the theory is that on 20 it is a bit long for resonance, which now 
> looks like a 3/8 wave.  Any antenna used on multiple bands will work 
> differently on each band.
> I am trying to understand at what point the SWR drastically effects the 
> efficiency of the vertical.  The variables seem to be reflected power and 
> transmitter shut back when it sees the reflected power.  That can be 
> eliminated with a tuner, but I don't know if doing that actually delivers 
> more signal to the antenna or not.  Working with shielded line and a tuner 
> is new to me.
> I am going to try a remote automatic tuner at the base of the antenna.  That 
> sounds like the best way to go for efficient multi-band operation.  I think 
> that with coax, the tuned reflected power probably warms the coax rather 
> than is radiated by the vertical.  It looks like stretching the efficient 
> use of the antenna from 17 meters to 29.2 for A.M. Phone is asking a lot, 
> which makes sense to me.