I am making a C130E HSI.It needs to be driven by GPS, VOR, TAC (faked with VOR2 if possible)1) I assume I use all the HSI_????? variables to drive the gauge elementsHSI_VERTICAL_NEEDLEHSI_HORIZONTAL_NEEDLEHSI_VERTICAL_VALIDHSI_HORIZONTAL_VALIDHSI_TF_FLAGHSI_OBI_NEEDLEHSI_DESIRED_HEADING_NEEDLEHSI_BEARINGHSI_BEARING_VALIDHSI_SIGNAL_LOCALISERHSI_SPEEDHSI_DISTANCEHSI_STATION_NAME...and then somehow set what drives the HSI variables? Is this a correct assumption.2) Does NAV1 automatically drive the HSI. Then I use GPS_DRIVES_NAV1 to make GPS drive NAV1 and thus drive HSI.3) If this is the case, when I set NAV1_FREQUENCY, NAV1_VOR_RADIAL, etc...HSI should update accordingly?4) If the rest of this is true, then NAV1 drives VOR1 and NAV2 drives VOR2, correct?I just want to make sure I am on the right track. If we get some of this documented I will organize it into a useful FAQ or guide! I just need to get some general idea how all these things are related. More to come...Thanks,Ryan

1)2)3)4:Yes.Apart from that try it out and you'll see it. Also have alook in the Baron HSI XML code, it isn't the same as C, but you get the idea prettya soon.Arne Bartels