Test Mode; Battery Shutoff Voltage Adjustment; Vcr Section Adjustments Jigs - Sharp VL-A111S/H/E Service Manual

5-4. TEST mode

TEST No. Title
1 Sensor Off
2 Mecha Adjustment mode
3 Shut Off Adjustment
4 Error Display
5 PASS mode
6 Cam Adjustment mode
7 VCR Adjustment mode
8 Head Switching Point ADJ.
Note: If "T-03" is selected in the CAM mode while a recordable tape is loaded, the unit starts recording automatically.
T-01

5-5. Battery shutoff voltage adjustment

1) Supply power to the main unit, using the variable-voltage DC power supply (range of 2.5V to 5.0V).
2) Set the CAM/OFF/VCR SW to CAM to switch to the camera mode.
3) Load a recordable tape and set the main unit to CAM REC. PAUSE.
4) Set the main unit to TEST mode No. 3, and start recording.
5) Measure voltage between TL2911(+) and TL2914(GND), and adjust the supply voltage to 3.1V.
6) The adjustment is complete if "BATTERY" is displayed on the monitor screen for a second when the PLAY key of operation unit
is pressed.
7) The adjustment is regarded as proper if the auto shut-off is actuated after the warning is displayed when the TEST mode is cancelled.
* In case of automatic adjustment of shut-off voltage, adjustment is impossible if voltage is above 3.1V ± 0.2V.
If the adjustment is made at 2.9V or below, the low-voltage operation may become unstable.
5-6. VCR section adjustments

5-6-1. VCR section adjustments jigs

• Measuring instruments:
*Color monitor TV set
*Digital voltmeter
*DC power supply
*Audio generator (CR oscillator)
*Alignment tape (JiGWR5-5CSP)
(JiGWR5-8CSE)
All the sensors are off except for the cassette control switch, DEW sensor, and battery
sensor.
ATF sampling is restricted to the central part.
Shutoff voltage value is written in E
—
Track shift (1/4 shift)
—
—
If "TEST 8" is selected for normal tape playback, Head Switching Pint is automatically
adjusted.
1 Select No with "FF" or "REW" key.
2 Confirm with "PB" key.
*Oscilloscope
*Frequency counter
*Signal generator
*AV output cable (accessory)
*Video recording tape
(For Y/C, audio and servo adjustments)
23
Contents
2
PROM.
*DC cable (AC adapter accessory)
*Video extension cables
*Vector scope
*AC adapter
VL-A111S/H/E/AH131S/H/E
VL-AH151S/H/E