TM 1–1520–238–T–320–3MULTIPLEX READ CODE INTERPRETATIONS20–1 SIGNAL NAME:DOP DRIFT VEL BCD 1 –999.9/ +999.9 KM/HR (–200/ +200)MEMORY LOCATION: 000447MEMORY DATA BIT(S):19–18(BINARY)CONDITION:If sixth digit displayed on HOD is 0, and fifth digit is 0, 1, 2, or 3=plus, north, west, up,If sixth digit displayed on HOD is 0, and fifth digit is 4, 5, 6, or 7=failurewarningIf sixth digit displayed on HOD is 1, and fifth digit is 0, 1, 2, or 3=no computed data andno failure detectedIf sixth digit displayed on HOD is 1, and fifth digit is 4, 5, 6, or 7=minus, south, east,down, fromSIGNAL FUNCTION:Indicates sign/status of Doppler.REMARKS: From Doppler through CPG MRTU Type III to FCC.PASS:If CONDITION agrees with Doppler drift, go to paragraph 20–2.FAIL: Location of fault: Doppler, wiring from Doppler to CPG MRTU Type III, CPG MRTU Type III.Troubleshoot wiring to isolate fault (TM 11–1520–238–23–2).20–2 SIGNAL NAME:DOP DRIFT VEL BCD 1MEMORY LOCATION: 000447MEMORY DATA BIT(S):15–12(HEX)CONDITION:If third digit displayed on HOD is 0, 1, 2, or 3, and fourth digit is 0=0 If third digit displayed on HOD is 4, 5, 6, or 7, and fourth digit is 0=1 If third digit displayed on HOD is 0, 1, 2, or 3, and fourth digit is 1=2SIGNAL FUNCTION:Indicates hundreds field.REMARKS: From Doppler through CPG MRTU Type III to FCC.PASS:If CONDITION agrees with drift velocity, go to paragraph 20–3.FAIL: Location of fault: Doppler, wiring from Doppler to CPG MRTU Type III, CPG MRTU Type III.Troubleshoot wiring to isolate fault (TM 11–1520–238–23–2).20–3 SIGNAL NAME:DOP DRIFT VEL BCD 1MEMORY LOCATION: 000447MEMORY DATA BIT(S):11–8(HEX)CONDITION:If second digit displayed on HOD is 0 or 1, and third digit is 0 or 4=0If second digit displayed on HOD is 2 or 3, and third digit is 0 or 4=1If second digit displayed on HOD is 4 or 5, and third digit is 0 or 4=2If second digit displayed on HOD is 6 or 7, and third digit is 0 or 4=3If second digit displayed on HOD is 0 or 1, and third digit is 1 or 5=4If second digit displayed on HOD is 2 or 3, and third digit is 1 or 5=5If second digit displayed on HOD is 4 or 5, and third digit is 1 or 5=6If second digit displayed on HOD is 6 or 7, and third digit is 1 or 5=7If second digit displayed on HOD is 0 or 1, and third digit is 2 or 6=8If second digit displayed on HOD is 2 or 3, and third digit is 2 or 6=9SIGNAL FUNCTION:Indicates tens field.REMARKS: From Doppler through CPG MRTU Type III to FCC.PASS:If CONDITION agrees with drift velocity, go to paragraph 20–4.FAIL: Location of fault: Doppler, wiring from Doppler to CPG MRTU Type III, CPG MRTU Type III.Troubleshoot wiring to isolate fault (TM 11–1520–238–23–2).