Garmin GNC 250 Maintenance And Repair Manual page 3

4.1 MEMORY BATTERY REPLACEMENT..................................................................................23
4.2 FINAL TEST..........................................................................................................................24
4.2.1 Test Equipment Required............................................................................................24
4.2.2 Set-Up..........................................................................................................................25
4.2.3 Final Test Procedure....................................................................................................25
4.2.4 Comm Transceiver Alignment....................................................................................41
5.1 LIST OF REPLACEABLE PARTS.........................................................................................45
5.2 ASSEMBLY DRAWINGS.....................................................................................................46
FIGURE 1 GNC 250/300 BLOCK DIAGRAM............................................................................3
FIGURE 2 CONTROL/DISPLAY UNIT BLOCK DIAGRAM.....................................................4
FIGURE 3 CPU BOARD BLOCK DIAGRAM.............................................................................5
FIGURE 4 RF/IF BLOCK DIAGRAM ........................................................................................7
FIGURE 5 COMMUNICATION TRANSCEIVER .....................................................................8
FIGURE 6 CPU BOARD TESTPOINTS (TOP VIEW)..............................................................12
FIGURE 7 CPU BOARD TEST POINTS (BOTTOM VIEW)....................................................13
FIGURE 8 COM RECEIVER TEST SETUP..............................................................................35
FIGURE 9 TRANSMITTER TEST SETUP...............................................................................39
FIGURE 10 J2 REAR CONNECTOR PINOUT DEFINITION..................................................43
FIGURE 11 J1 REAR CONNECTOR PINOUT DEFINITION..................................................44
FIGURE 12 GNC 250/300 ASSEMBLY DRAWING (VIEW 1).................................................47
FIGURE 13 GNC 250/300 ASSEMBLY DRAWING (VIEW 2).................................................48
FIGURE 14 GNC 250/300 ASSEMBLY DRAWING (VIEW 3).................................................49
FIGURE 15 GNC 250/300 ASSEMBLY DRAWING (VIEW 4).................................................50
FIGURE 16 GNC 250/300 ASSEMBLY DRAWING (VIEW 5)................................................51
FIGURE 15 GNC 250/300 CONNECTOR DIAGRAM ..............................................................52
SECTION 4
SERVICE AND TESTING
SECTION 5
ILLUSTRATED PARTS LIST
LIST OF FIGURES
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