- The current (seen) TP on the "Antenna Setup" might not be an active one, so when you do the power search, it actually scans not only this inactive TP but also others TPs (not seen) which are active. That is why you found NASA and D121,...So it is not strange here ... (IMO)
- 121.0°W is not your true south, but you are close, though!
Make sure your dish points at 180° - 17.2° = 162.8° according to your compass, select G10R in the "Antenna Setup" menu, go to "TP" item and select 11720V/27692 (because I know this is active), select USALS and enter your Long/Lat, then hit "Move". From now on, just fine tune your dish pointing until you see the green bar on top (this is for "Fortec Star Ultra Liftime" receiver)
I like the simple instructions in the following PDF that Mr. PSB posted earlier....
http://www.adventistsat.com/downloads/InstallDiSEqC.pdf
Normally, with USALS, once you get that G10R, you're done! Just go to the others sats, and change "Positioner Settings" to USALS. That's it.
This is just my tiny experience...and thank for any correction from other experts.