Vor/Loc Receiver Testing - Garmin GNS 400W Series Maintenance Manual

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4.6

VOR/LOC RECEIVER TESTING

4.6.1 Standard Loads
NAV Receiver Antenna
The NAV receiver antenna J5 must operate in a 50 ohm load.
NAV Course Deviation Deflection Load (NAV +LEFT)
One standard CDI deflection load is 1000 ohms. Three standard loads must be connected
between NAV +LEFT J6-5 and NAV +RIGHT (NAV COMMON) J6-6.
NAV Course Deviation Flag Load (NAV +FLAG)
One standard CDI flag load is 1000 ohms. Three standard loads must be connected between
NAV +FLAG J6-3 and NAV -FLAG (NAV COMMON) J6-4.
NAV To/From Load (NAV +TO)
One standard To/From load is 200 ohms. Three standard loads must be connected between NAV
+TO J6-1 and NAV +FROM (NAV COMMON) J6-2.
NAV Composite Video Load (NAV COMPOSITE OUT)
One standard composite video load is 10,000 ohms connected between NAV COMPOSITE OUT
J6-8 and GND J6-41.
NAV Super Flag Load (NAV SUPER FLAG OUT)
One standard super flag load is 56 ohms connected between NAV SUPER FLAG OUT J6-15 and
GND J6-41.
G/S Super Flag Load (G/S SUPER FLAG OUT)
One standard super flag load is 56 ohms connected between G/S SUPER FLAG OUT J6-38 and
GND J6-41.
ARINC 429 Transmitter Load (VLOC 429 OUT A/OUT B)
The standard ARINC 429 transmitter load is 2.4K ohms resistance and 250 pF capacitance
between the differential outputs VLOC 429 OUTA J6-24 and VLOC 429 OUTB J6-23, and 2.4K
ohms resistance and 250 pF capacitance connected from each of the outputs to ground.
RS232 Transmitter Load (VLOC SERIAL OUT)
The standard RS232 transmitter load is 3000 ohms measured from the RS232 serial output to
ground. One standard load is connected between VLOC SERIAL OUT J10-10 and GND J10-4.
Page 4-44
Rev. A
GNS 400W Series Maintenance Manual
190-00356-05