COMPLIANCE
Mandatory
PURPOSE
Some GTN 650 and GTN 750 Navigation Systems require either upgrading to Mod Level 1 to improve the reliability of the VHF navigation receiver, or marking of Mod Level 1 on the serial tag to indicate the previously upgraded, but unmarked Mod Level status.
PRODUCTS AFFECTED
All GTN 650/750 Units that have not been verified as having been upgraded to Mod 1.
DESCRIPTION
Service Bulletin 1203 provides instructions to inspect the serial number of the GTN 650/750 to determine its disposition as related to the Mod Level 1 requirement.