Yesterday I wrote:
It just occurred to me that I can use direct serial port commands to the ST2 to test that the azimuth rotor moves CCW from, say, 175 deg to 185 deg, and does not try to go CW through the rotor stops. Repeating with SatPC32 interface should verify I have the azimuth stops set correctly without having to wait for a suitable satellite pass. I am hoping this may have something to do with flip mode being triggered. Or it may just give me something to try between satellite passes until I figure it out!
I think I figured it out.....and SatPC32 is behaving correctly. SatPC32 will use flip mode at AOS when the azimuth range of a pass goes through the rotor's South stop (in my case). There were several passes last night that ranged from around 165-175 degrees azimuth at AOS to 270-350 degrees at LOS. Flip mode lets SatPC32 use an azimuth range of 345-170 degrees (think of it as 345-530) to avoid the rotor South stop limit. Restarting SatPC32 once the satellite was at an azimuth above 180 degrees seemed to confirm this behavior (I need to test again to be sure).
73, Steve KS1G at a.m.s.a.t dot org