[Elecraft] Antenna Analyzer sensitivity to near-field effects

[Stuart Rohre]

Hmm, I am not sure what that would mean, an analyzer that can see near field 
effects.

The in line analyzers indirectly might show near field effects simply by 
being interfered with by strong RF nearby.

Almost anywhere on the boat that is away from structure and conductors will 
have the same HF efficiency, if a full size HF antenna, or nearly so.

To really have differing efficiency, you would have to be able to move 
things at least a quarter to half wave to see an effect.  I am thinking you 
mean a pleasure boat and not a larger yacht.   Most small boats just don't 
give you many options.   You probably need to place the vertical well aft, 
out of the way of sail apparatus if a sail boat.  On a motor boat, you could 
be anywhere along the center line.  Probably the most important efficiency 
aid is to have wide straps going to a keel ground plate or plates.  The more 
metal in contact with the water the better.

Most sail boats have a very effective/ efficient antenna in loading the back 
stay guy of the mast as a sloper, rather than using a true vertical.  Such 
an antenna will have some vertical and thus low angle take off component off 
the beam of the boat.

Stuart
K5KVH