Re: Zaxcom range

Hi Billy,
Doubling range requires 6 dB (4 times the power) not 9 dB (8 times the
power). It's the surface of the sphere (grows by the square of
distance), not the volume (cube) of the sphere that is important.
Antenna power level at a given distance is determined by what energy
passes through an area of the sphere intercepted by the antenna. Since
the total spherical area grows by the square of the distance, the
fraction of the power that is intercepted by the antenna decreases by
the square of the distance.
Best Regards,
Larry Fisher
Lectrosonics

On 2 May 2007 08:36:51 -0700, Billy Sarokin <bigmaho@xxxxxxxxxxx>
wrote:

Had to dig out my old ham radio books to refresh my memory. To
theoretically double your range you'd need a 9db boost in the power
output (at 50mw, +9db would = 400 mw). Doubling your power (from
50-100 mw) gives you a 3db increase which depending on if you use a
logrithmic scale or a straight scale would give you either a 12.5%
increase in range or a 30% increase. Back to the real world. My
earlier Zaxcom transmitters have user selectable power output settings
from 1mw to 100mw. I usually kept them set at 50mw but if I was
fighting range, I'd increase them to 100 mw. I found it made
relatively little difference, so I'll stay with the lower end of my
projection of approx 10% real world. Any of our rf mavens on line?
Billy Sarokin


On May 2, 10:49 am, Fernando <f...@xxxxxx> wrote:
I thought that doubling the RF power should give you 20-25% more
range...

.

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