[TenTec] grounding dipoles

[Ken Brown]

>  - the main reason I ask is the antenna switch I have connects the 
> center and shield to ground when they are not selected on the switch, 
> in essence creating ground radials fairly close to the active dipole.

Not exactly ground radials, assuming there is some feedline distance 
between the switch and the dipoles, the "grounded" antennas are not at 
RF ground potential at all. Remember that a short circuit at one end of 
a feedline looks like an open circuit a quarter wavelength (or odd 
multiple thereof) down the line. Or an open circuit looks like a short a 
quarter wavelength down the line.

As someone else has already suggested, you could have connected all of 
the dipoles to a common feedpoint and it would probably work fine. 
However, since you've already put the labor and materials into separate 
feedlines for the three dipoles, I suggest you do some experimenting 
with it. See what happens with various combinations of some of the 
feedlines shorted and some of them open. Or connect them all together 
(or just some of them) with 'tee' connectors. You might get some 
desireable effects. You might find that one configuration reduces 
interference from a certain source, or you might find a configuration 
that gives you some gain in a desired direction.

DE N6KB