> Okay, I had one guy email me with a comment that if I have one
> beverage, then I will probably want more. Now I need to ask about
> feeding multiple beverages. Can I locate the feedpoints at one
> location and switch the beverage wires with relays to one transformer,
> or do I need to feed them all individually and then switch between the
> feedlines?
Unless you really know what you are doing with RF layouts, you never
want to switch high impedance lines! Finding relays that have good
isolation is even more of a problem when impedances are high, let
along the general layout. Because of that, you always want to use
separate transformers and switch the low impedance side with
directional antennas.
It is also a good idea to use separate grounds for the antennas and
keep the feedpoints isolated by using isolation-type matching
transformers. A deep ground rod in good soil will allow up to 20dB of
crosstalk between antennas sharing that same ground, and the problem
gets worse when the ground connection is poor. Either use a very
good ground with short leads or keep the small grounds separated from
each other.
Of course if the antenna is not very directional and/or you aren't
terribly concerned about maximizing performance, you can break the
general rules.
73, Tom W8JI
W8JI@contesting.com
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