Yaesu FTA-850L Operating Manual page 41

z Reading the CDI
 If the OBS is set to 50° and your aircraft is at 230°
from a certain VOR station, for example, you are
"on course" and the course deviation needle of the
CDI will be at the center of the compass rose.
N
Magnetic
North
VOR
Station
 If the OBS is set to 50° but your aircraft is at 236°
from a certain VOR station, for example, you are
"off course" and the course deviation needle of the
CDI will be inside the right half of the compass rose.
N
Magnetic
North
VOR
Station
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