JVC VF-P116U Service Manual page 17

Measuring
No. Item instruments &
Input signals
2.3 CHECK OF SUPPLY VOLTAGE
1 12V supply • Digital voltmeter
voltage check
2.4 ADJUSTMENT OF H.HOLD
1 H. HOLD • Frequency
adjustment counter
2.5 ADJUSTMENT OF V.HOLD
1 V.HOLD • Oscilloscope
adjustment (V-rate,10:1)
2.6 ADJUSTMENT OF VIDEO LEVEL
1 Video level • Gray scale chart
adjustment • Oscilloscope
(H-rate,10:1)
4
Measuring point ( * )
Adjustment parts ( - )
Adjustment level ( + )
* Between pin 5 of CN1 and
GND [MAIN]
+ +12V ± 0.5V
* Between collector of Q10
[MAIN] and TP3(GND)[VR]
- H. HOLD(VR3)[MAIN]
+ 14.4 to 15kHz
* TP2 and TP3 (GND)[VR]
- V. HOLD(VR5)[MAIN]
+ 17 to 18ms(U.Ver)
+ 20.5 to 21.5ms(E.Ver)
* TP1[MAIN] and TP3
(GND)[VR]
- VIDEO LEVEL(VR101)
[MAIN]
+ +10 ± 0.5V DC
Adjustment procedure
1) Check to see if the specified voltage is meas-
ured at the measuring point.
1) Adjust VR3 to obtain the specified frequency
at the measuring point.
1) Adjust Vr5 to obtain the specified level at the
measuring point.
17.5 ± 0.5ms(U.Ver)
21 ± 0.5ms(E.Ver)
1) Shoot the gray(scale) chart by the camera.
2) Observing the waveform on oscilloscope, ad-
just VR101 to obtain the specified level at the
measuring point.
+10 ± 0.5V DC
0V DC