TM 1–1520–238–T–3
14–14
Change 4
14–50 SIGNAL NAME:
VIDEO SYNC SELECT (ACY) SYNC SEL CTL (ACZ)
MEMORY LOCATION: 000654
MEMORY DATA BIT(S):
14
(BINARY)
CONDITION:
If second digit displayed on HOD is 0, 1, 2, or 3 =PNVS
If second digit displayed on HOD is 4, 5, 6, or 7 =TADS
SIGNAL FUNCTION:
Selects sync for symbol generator.
REMARKS: From FCC to symbol generator.
PASS:
Location of fault if CONDITION corresponds to selected sync pulse: replace symbol generator
(TM 11–1520–238–23–2).
FAIL: Location of fault: replace FCC (TM 9–1230–476–20–1).
14–51 SIGNAL NAME:
INTERNAL BIT CMD
MEMORY LOCATION: 000654
MEMORY DATA BIT(S):
19
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Commands symbol generator to perform built–in–test (BIT).
REMARKS: From FCC to symbol generator.
PASS:
Location of fault if first digit displayed on HOD is 0, 2, 4, or 6: replace symbol generator
(TM 11–1520–238–23–2).
FAIL: Location of fault: replace FCC (TM 9–1230–476–20–1).
14–52 SIGNAL NAME:
CPG SYM MODE
MEMORY LOCATION: 000655
MEMORY DATA BIT(S):
4–7
(HEX)
CONDITION:
If fifth digit displayed on HOD is 1=NONE
If fifth digit displayed on HOD is 2=PLT
If fifth digit displayed on HOD is 3=CPG
If fifth digit displayed on HOD is 4=STATUS
SIGNAL FUNCTION:
Selects CPG symbology display.
REMARKS: From FCC to symbol generator.
PASS:
If CONDITION corresponds to selected symbology mode go to paragraph 14–232.
FAIL: Location of fault: refer to Chapter 25, paragraph 25–18.
14–53 SIGNAL NAME:
CPG VIDEO MODE
MEMORY LOCATION: 000655
MEMORY DATA BIT(S):
8–11
(HEX)
CONDITION:
If fourth digit displayed on HOD is 0 and third digit displayed
on HOD is 4 or 5 =TV
If fourth digit displayed on HOD is 1 and third digit displayed
on HOD is 0 or 1 =FLIR
If fourth digit displayed on HOD is 1 and third digit displayed
on HOD is 4 or 5=PNVS
If fourth digit displayed on HOD is 2 and third digit displayed
on HOD is 0 or 1 =REC
If fourth digit displayed on HOD is 2 and third digit displayed
on HOD is 4 or 5 =NOT SELECTED
SIGNAL FUNCTION:
Selects CPG video symbology display inputs.
REMARKS: From FCC to symbol generator.
PASS:
Location of fault if CONDITION corresponds to selected symbology mode: replace symbol
generator (TM 11–1520–238–23–2).
FAIL: Location of fault: refer to Chapter 25, paragraph 25–8.
