PHG circles

[Dave Hernandez]

Currently aprs.fi shows PHG circle offsets (gain direction for APRS) as a cardioid pattern.  Looking at the APRS specifications, it appears that they are just supposed to be a circle, simply offset by 1/3rd.  

"The Directivity code offsets the PHG circle by one third in the indicated

direction. This means a front-to-back ratio of 2 to 1." -- APRS 1.0.1, chpt 7 (p 28)

[Heikki Hannikainen]

Yes. But, with a lot of overlapping circles, it's a bit hard to see which
circle refers to which station, and where they're pointing. So, I went for
a cardioid instead, it works better.

There are quite a few other shortcomings in the 1.0.1 spec too, not
everything is really implemented exactly like it says in there.

- Hessu