[aprssig] PHG calculators

[Jack Spitznagel]

Sounds like some folks are asking for something like the six digit 
extension PHG's (PHGDRA/ - Power,Height,Gain,Directivity,Rate,Altitude) 
that are used by the PropNET Project folks. The altitude of terrain is 
supposed to help to differentiate between what the listener stations 
receive when comparing the guy in the valley using his tower as a 10 M 
vertical and the guy on the mountain top using a retuned CB vertical. It 
does not have a front to back value in it either.

So my beacon text on Propnet is "kd4iz>hy:[fm19oo]phg221066/^967D" Using 
a QRP radio 40ft vertical with unity gain, omnidirectional pattern, rig 
beaconing every 10 minutes, antenna parked in the yard where the ASL 
height is 680ft.
Obvious... the rest is my call, band (hy = 10M), my locator FM19oo, and 
the ^967D  at the end is a checksum that helps us analyze the path 
quality by verifying the data was copied accurately.

Reminds me to ask why we don't have a front-to-back ratio value for 
beams and arrays... although it may be not that useful for PropNET. Most 
folks use verticals which are unity and direction neutral because we are 
probing in all directions...