Hitachi VM-H675LA Service Manual page 98

Part Display
Trouble RST
sensor
ESS
EST
Tape TAB
detection
switches, ME
etc.
MP
STG
Capstan CFG
motor
Cylinder S30
Mechanism UST
mode
switch REW
LST
FWD
HEC
EJT
Table 1-3 Results of B Mode Self-Diagnosis (2/2)
Results of diagnosis
(Detect display conditions)
The pulse from the take-up reel sensor is
defective.
(There is one pulse or less within two
seconds.)
The pulse from the supply end sensor is
defective. (No pulse is input for more than
100 ms continuously within two seconds.)
The pulse from the take-up end sensor is
defective. (No pulse is input for more than
100 ms continuously within two seconds.)
The erase prevention tab detection switch
detects the record inhibit state (OFF).
The ME/MP tape detection switch detects
the MP state (OFF).
The Hi-8 MP tape detection switch detects
the normal MP state (OFF).
The cassette holder switch detects the state
where the cassette holder is not lowered
(OFF).
The CAPST. FG pulse is defective.
(150 pulses or less within two seconds.)
The SW30/25 (CYL. FG) pulse is defective.
(No pulse is input normally within two
seconds.)
The unloading stop position detection signal
is defective.
The rewind position detection signal is
defective.
The loading stop position detection signal is
defective.
The play or fast forward position detection
signal is defective.
Between the fast forward position and unloading
stop position detection signal isdefective.
The eject position detection signal is
defective.
Parts/circuits deemed to be defective
Take-up reel disk
Trouble sensor (reel sensor)
Capstan motor
IC0901
Trouble sensors (end sensor/end LED)
Q0905
IC0901
DC-DC converter circuit (B+ line)
Trouble sensors (end sensor/end LED)
Q0905
IC0901
DC-DC converter circuit (B+ line)
Caution: These switches flash when they are
not pressed.
It is abnormal if they flash when
pressed.
Trouble sensor
IC0901
Capstan motor
IC0651
IC0901
DC-DC converter circuit
Cylinder
IC0631
IC0901
DC-DC converter circuit
Caution: The positions shown on the left are
detected in the order described
within 10 seconds.
Mechanism mode switch
Trouble sensor
IC0901
Defective rotation/phase of drive gears in
mechanical block.
Loading motor.
Tape transport components.
Guide roller rails
DC-DC converter circuit.
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