JVC DR-MV5BEK Page 18 Service Manual Download

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1-18 (No.YD075)

5.3.4 EMG content description
Note:

EMG contents “E09” are for the model with Dynamic Drum (DD).

If the mechanism mode does not change to the next mode within 4 sec-

onds after the loading motor starts rotating in the loading direction, while

the mechanism is in the after-loading position (with the tape up against

the pole base), [E:01] is identified and the power is switched OFF.

However, if the tape loading is not completed within 4 seconds after

the loading motor starts rotating in the loading direction, the tape is

simply unloaded and ejected. No EMG data is recorded in this case.

When the mechanism mode cannot be changed to another mode

even when the loading motor has rotated for more than 4 sec-

onds in the unloading direction, [E:02] is identified and the power

is turned off.

When the falling edje of the take-up reel pulse has not been gen-

erated for more than 4 seconds in the capstan rotating mode,

[E:03] is identified, the pinch rollers are turned off and stopped,

and the power is turned off. In this case, however, the mecha-

nism should be in position after tape loading. Note that the reel

EMG is not detected during Slow/Frame advance operations.

When the drum FG pulse has not been input for more than 3 sec-

onds in the drum rotating mode, [E:04] is identified, the pinch roll-

ers are turned off and stopped, and the power is turned off.

If the cassette does not reach the eject position within about 0.7

seconds after the cassette housing has started the cassette ejec-

tion operation, [E:05] is identified, the drive direction is reversed

to load the tape, the mode is switched to STOP mode with the

pinch roller OFF, and the power is switched OFF.

During the cassette insertion process, the drive direction is reversed

and the cassette is ejected if the tape is not up against the pole

base within about 3 seconds after the start of the cassette pulling-

in operation. If the cassette does not reach the eject position within

about 0.7 seconds after the drive mode reversal operation, [E:05]

is identified and the power is switched OFF immediately.

When the capstan FG pulse has not been generated for more

than 1 second in the capstan rotating mode, [E:06] is identified,

the pinch rollers are turned off and stopped, and the power is

turned off.However, the capstan EMG is not detected in SLOW/

STILL modes.

Note that, if the part number of the System Control IC begins with

"MN" or "M3", the capstan EMG is not detected even during the

FF/REW operation.

When short-circuiting of the SW power supply with GND has lasted

for 0.5 second or more, [E:07] is identified, all the motors are

stopped and the power is turned off.

When the DD FG pulse is not generated within 2.5 seconds, [E:09]

is identified, the tilt motor is stopped and the power is turned off.

When the falling edge of the supply reel pulse has not been gen-

erated for more than 10 seconds in the capstan rotating mode,

[E:0A] is identified and the cassette is ejected (but the power is

not turned off). In this case, however, the mechanism should be

in the position after tape loading (with the tape up against the pole

base). Also note that the reel EMG is not detected during Slow/

Frame advance operations.

1. The mechanism is locked in the middle of the mode transition during a tape loading operation.

2. The mechanism overruns during the tape loading operation because the SYSCON cannot recognize

the mechanism mode normally. This problem is due to a cause such as a rotary encoder failure.

3. Power is not supplied to the loading MDA. (M12V/Vcc/Vref/ICP are disconnected in the middle.)

1. The mechanism is locked in the middle of mode transition.

2. Without an eject signal being sent from the SYSCON, unloading is attempted (i.e. Ejection is attempted

while the tape is still inside the mechanism.) because the SYSCON cannot recognize the mechanism

mode normally. This is due to a cause such as a rotary encoder failure. (Mechanism position:

UPPER)

3. Power is not supplied to the loading MDA. (M12V/Vcc/Vref/ICP are disconnected in the middle.)

1. The take-up reel pulse is not generated in the FWD transport modes (PLAY/FWD SEARCH/FF,

etc.) because;
1) The idler gear is not meshed with the take-up reel gear because the mechanism mal-functions for

some reason.

2) The idler gear is meshed with the take-up reel gear, but incapable of winding due to too large

mechanical load (abnormal tension);

3) The reel is rotating normally but an FG pulse is not generated due to the take-up reel sensor failure.

2. The supply reel pulse is not generated in the REV transport modes (REV SEARCH/REW, etc.)

because;
1) The idler gear is not meshed with the supply reel gear because the mechanism mal-functions for

some reason.

2) The idler gear is meshed with the supply reel gear, but incapable of winding due to too large a

mechanical load (abnormal tension);

3) The reel rotates normally but the FG pulse is not generated due to a supply reel sensor failure.

3. Power(SW5V) is not supplied to the reel sensor on the tape winding side.

1. The drum could not start or the drum rotation has stopped due to too large a load on the tape,

because;

1) The tape tension is abnormally high;

2) The tape is damaged or a foreign object (grease, etc.) adheres to the tape.

2. The drum FG pulse did not reach the System controller CPU because;

1) The signal circuit is disconnected in the middle;

2) The FG pulse generator (hall device) of the drum is faulty.

3. The drum control voltage (DRUM CTL V) is not supplied to the MDA.

4. Power (M12V) is not supplied to the drum MDA.

1. The cassette cannot be ejected due to a failure in the drive mechanism of the housing.

2. When the housing load increases during ejection, the loading motor is stopped because of lack of

headroom in its drive torque.

Housing load increasing factors: Temperature environment (low temperature, etc.), mechanism

wear or failure.

3. The sensor/switch for detecting the end of ejection are not functioning normally.

4. The loading motor drive voltage is lower than specified or power (M12V) is not supplied to the

motor (MDA).

5. When the user attempted to eject a cassette, a foreign object (or perhaps the user's hand) was

caught in the opening of the housing.

1. The capstan could not start or the capstan rotation has stopped due to too large a load on the tape,

because;

1) The tape tension is abnormally high (mechanical lock);

2) The tape is damaged or a foreign object (grease, etc.) is adhered to the tape (occurrence of tape

entangling, etc.).

2. The capstan FG pulse did not reach the System controller CPU because;

1) The signal circuit is disconnected in the middle;

2) The FG pulse generator (MR device) of the capstans is faulty.

3. The capstan control voltage (CAPSTAN CTL V) is not supplied to the MDA.

4. Power (M12V, SW5V) are not supplied to the capstan MDA.

1. The SW 5 V power supply circuit is shorted with GND.

2. The SW 12 V power supply circuit is shorted with GND.

1. The DVD unit is defective.

2. Contact failure of the wires in the DVD unit or VHS side.

1. The FG sensor is defective. (The soldered parts have separated.)

2. The pull-up resistor at the FG sensor output is defective. (The soldered parts have separated.)

3. Contact failure or soldering failure of the pins of the connector (board-to-board) to the FG sensor.

4. The power (5V) to the sensor is not supplied. (Connection failure/soldering failure)

5. The FG pulse is not sent to the System Controller CPU.

6. The tilt motor is defective. (The soldered parts have separated.)

7. The drive power to the tilt motor is not supplied. (Connection failure/soldering failure)

8. The tilt motor drive MDA - IC is defective.

9. Auto-recovery of the DD tilting cannot take place due to overrun.

1. The supply reel pulse is not generated in the FWD transport mode (PLAY/FWD SEARCH/FF,

etc.) because;

1) PLAY/FWD or SEARCH/FF is started while the tape in the inserted cassette is cut in the middle;
2) A mechanical factor caused tape slack inside and outside the supply reel side of the cassette shell.

In this case, the supply reel will not rotate until the tape slack is removed by the FWD transport,

so the pulse is not generated until then;

3) The reel is rotating normally but the FG pulse is not generated due to a supply reel sensor failure.

2. The take-up reel pulse is not generated in the REV transport mode (REV SEARCH/REW, etc.).

1) REV SEARCH/REW is started when the tape in the inserted cassette has been cut in the middle;
2) A mechanical factor caused tape slack inside and outside the take-up reel side of the cassette

shell. In this case, the take up will not rotate until the tape slack is removed by the REV transport,

so the pulse will not be generated until that time;

3) The reel is rotating normally but the FG pulse is not generated due to a take-up reel sensor failure.

3. The power (SW 5V) to a reel sensor is not supplied.

FDP

CONTENT

CAUSE

Presupposing the presence of the control pulse output in the PLAY mode, when the value obtained by mixing the two V.FM output channels (without regard

to the A.FM output) has remained below a certain threshold level for more than 10 seconds, [E:U1] is identified and recorded in the emergency history.

During the period in which the head clog is detected, the FDP shows "U:01" and the OSD repeats the "3 seconds of warning display" and the "7 seconds of

noise picture display" alternately.

EMG code : "E:C1" or "E:U1" / FDP : "U:01" / OSD : "Try cleaning tape." or "Use cleaning cassette."

The head clog warning is reset when the above-mentioned threshold has been exceeded for more than 2 seconds or the mode is changed to another mode

than PLAY.

EU1:
Head clog warning
history

E0A: Supply Reel

Pulse EMG

E07: SW Power

Short-Circuit

EMG

E06: Capstan FG

EMG