It should all be this easy! <GNS430 CDI Error in VOR mode>

[0TreeLemur]

So, on an IFR training flight last week my instructor noted a large (~30-deg.) discrepancy between the two VOR receivers in my aircraft.  The next flight we went to KMEI where there is a VOR test point on the field, and saw that the NAV receiver in the GNS430W is about 30-degrees off.  The other NAV rcvr in the KX-155 is within two degrees (yeah!). 

Yesterday I called a nearby avionics shop and discussed with a technician I know, who told me that the GNS430W probably required calibration of the CDI it is attached to, and told me something to try.  I went to the hangar, followed his instructions, which took about 5 minutes, and then went for a test flight.  Both NAV receivers now agree within 1 degree of each other!  

Solution: press and hold "Enter" while powering up the GNS 430W.  That boots it into calibration mode.   About 8 or 10 pages into the calibration mode is an option to "Calibrate 150 degrees CDI".  Set the CDI to 150 degrees "TO", highlight the box that says "Calibrate 150 degrees CDI"  and press enter.  That's it.   Not sure why it was off, but it is fine now.

It should all be that easy!

[Marauder]

It is amazing how easy some fixes are — provided you know where to find the answer. I still do the airborne VOR tests per 91.171 and love seeing the digital radios consistently showing 0 degree differences.

The first couple of times this happened, I went to a VOT to confirm I wasn’t seeing things.


Sent from my iPad using Tapatalk Pro