APRS-SCS Setup Power Height Gain Help

Power Height Gain
Click on the down arrow next to each drop down list box and select the item that
applies to your station.

Description of Power Height Gain from the APRSdos Docs. (Protocol.txt)
POWER-HEIGHT-GAIN: This optional field replaces the CSE/SPD fields with a
report of transmitter power, antenna height-above-average-terain and
antenna gain. APRS uses this to plot radio range circles around all
stations. The following details the format to be used in the BText of
a TNC dedicated as an APRS digipeater:

PHG5360
As you can see by the integers in the PHG string, there are only 10
possible values for each of these fields as follows:

DIGITS 0 1 2 3 4 5 6 7 8 9 Equation
-------------------------------------------------------------------
POWER 0, 1, 4, 9, 16, 25, 36, 49, 64, 81 watts SQR(P)
HEIGHT 10,20,40, 80,160,320,640,1280,2560,5120 feet LOG2(H/10)
GAIN 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 dB
DIR omni,45,90,135,180,225,270, 315, 360, . deg (D/45)

The DIRECTIVITY field offsets the PHG circle by one third in the
indicated direction. This means a front to back range of 2 to 1.
Most often this is used to indicate a favored direction or a null
even though an OMNI antenna is at the site. Note that 0 means
OMNI and 8 means 360 or a NORTH offset.

HIGHTS are ABOVE-AVERAGE TERRAIN! Not above ground or sea
level. ALso, since DOS version 8.0 the Height character may be any
ascii character 0-9 and above. This is so that higher heights for
aircraft or satelites may be incorportated.

On receipt, the PHG values are converted to a usable radio range using
the following algorithms:

POWER = P^2
H = 10 as a default
H = ASCII(Hchar)-51 converts it to a decimal value
HAAT = 10*2^H
GAIN = 10^(G/10) converts from DB to decimal
RANGE = SQR(2*H*SQR((P/10)*(GAIN/2)))

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