[Amps] Antenna vs. amp (was: al-1200 question)

Tom Rauch W8JI@contesting.com
Thu, 14 Mar 2002 22:02:50 -0500

> By the "same directional properties" I meant that they will have the
> same total beam width exposure to the sky. (not necessarily in the
> same direction) This total beam width is the sum of both vertical and
> horizontal beams.

I know what you are trying to say, but that still is not true. 
Efficiency can be different and/or considerable power can go into 
spurious lobes on one and not the other.

For example, Rhombics have very poor efficiency and many minor 
lobes, and have a very narrow sinX/X pattern shape for the same 
gain as other antennas. 
> If you add up all of the area of the sky that each antenna beam is
> exposed to due to each ones horizontal and vertical beam widths, I
> think you will find that given the same gain for each they will also
> have equal total exposure area.

Only when efficiency is the same....and it also only works when 
noise is uniformly distributed...which it almost never is.
73, Tom W8JI