JVC GY-HM790U Service Manual page 20

Measuring
No. Item Instruments &
Input Signals
3 Note:
Before proceeding to perform the BLACK adjustment, be sure to warm up the OP Block for 15 minutes or more.
BLACK Waveform
adjustment monitor
[60](NTSC) (Oscilloscope)
Approx.
0 to 50mV
4 BLACK Waveform
adjustment monitor
[50](PAL) (Oscilloscope)
[40]
[48]
1-20 (No.HC034<Rev.001>)
Measuring Point (A)
Mode Adjustment Points (B)
Adjustment Level (C)
ADJUST MENU (A)Y/VIDEO OUT
No.32 "BLACK (75Ω terminated)
[G] R" (B)[Cross-Shaped]
GAIN: 18dB (UP/DOWN)
button
(C)Minimize the level
difference between
left and right side.
ADJUST MENU (A)Y/VIDEO OUT
No.34 "BLACK (75Ω terminated)
[B] R" (B)[Cross-Shaped]
GAIN: 18dB (UP/DOWN)
button
(C)Minimize the level
difference between
left and right side.
ADJUST MENU (A)Y/VIDEO OUT
No.36 "BLACK (75Ω terminated)
[R] R" (B)[Cross-Shaped]
GAIN: 18dB (UP/DOWN)
button
(C)Minimize the level
difference between
left and right side.
ADJUST MENU (A)Y/VIDEO OUT
No.32 "BLACK (75Ω terminated)
[G] R" (B)[Cross-Shaped]
ADJUST MENU (UP/DOWN)
No.34 "BLACK button
[B] R" (C)Minimize the level
ADJUST MENU difference between
No.36 "BLACK left and right side.
[R] R"
Adjustment Procedure
(1) Select ADJUST MENU No.32 "BLACK [G]
R".
(2) Shoot the White chart (light box), and set
the Y level to 50mV.
(3) Setting switches
GAIN : H
ND FILTER : 1/16
(4) Push the [Set] button so that "*" lighting.
(5) Push the [Cross-Shaped](UP/DOWN) but-
ton so that the right side level should be
same as the left side.
(6) Push the [Set] button to store the adjust-
ment data.
(7) Select ADJUST MENU No.34 "BLACK [B]
R".
(8) Shoot the White chart (light box), and set
the Y level to 50mV.
(9) Push the [Set] button so that "*" lighting.
(10) Push the [Cross-Shaped](UP/DOWN) but-
ton so that the right side level should be
same as the left side.
(11) Push the [Set] button to store the adjust-
ment data.
(12) Select ADJUST MENU No.36 "BLACK [R]
R".
(13) Shoot the White chart (light box), and set
the Y level to 50mV.
(14) Push the [Set] button so that "*" lighting.
(15) Push the [Cross-Shaped](UP/DOWN) but-
ton so that the right side level should be
same as the left side.
(16) Push the [Set] button to store the adjust-
ment data.
Note:
When adjusting the Y level of the lens iris
from 0mV to 200mV, confirm that the level
difference between left and right are 5mV or
less.
If it is not, adjust the BLACK adjustment
again.
(1) Select ADJUST MENU No.1 "VIDEO
MODE CHANGE" and Change the VIDEO
MODE to [50](PAL). Perform black adjust-
ment in the same way as [60](NTSC)
(2) Select ADJUST MENU No.1 "VIDEO
MODE CHANGE" and Change the VIDEO
MODE to [40]. Perform black adjustment in
the same way as [60](NTSC)
(3) Select ADJUST MENU No.1 "VIDEO
MODE CHANGE" and Change the VIDEO
MODE to [48]. Perform black adjustment in
the same way as [60](NTSC)