[TowerTalk] Two signals on the same frequency?

[Jim Lux]

On 8/14/11 2:23 PM, Jim Brown wrote:
> On 8/14/2011 1:48 PM, Chet wrote:
>> A hypothetical question:
>
> Study the fundamentals of antennas, antenna arrays, and fields in the
> ARRL Handbook and ARRL Antenna Book. The short answer is that the
> signals from multiple antennas will ADD algebraically, taking their
> magnitude and phase into account. That is, in some directions they will
> be exactly in phase and will be stronger, in other directions they will
> be varying degrees of out of phase and either add less, or cancel each
> other. if they are equal in level and 180 out of phase, they will cancel
> perfectly.

And, if you have two separate transmitters, odds are that their crystal 
reference isn't going to track exactly, so the relative phasing will 
change with time.  Sort of like transmitting a fading signal from the 
get-go.