Onwa KR-1338, Service Manual

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VIDEO AMP
ANTI-LOG
J52
VIDEO IN
< 2
VR3
VIDEO
LEVEL
A/C
RAIN,
GAIN
A/C
SEA
BEARING P
HEADING P
JS2
JS2
3
4
Clutter level
TP7
Video level
TP5 Gain preset
TP3
Video Out
TP2
STC
Curve
TP4
VR1
GAIN
PRESET
VR2
STC
CURVE
STC
12V
S
C
A
N
A
/C
A
U
T
O
S
T
C
T
R
IG
VIDEO Signal adjustment
VIDEO signal adjustment is carried out in the processor board. This is a simplified
block diagram of the video amplified circuit.
Video level Conditions
A/C AUTO OFF
A/C SEA fully counterclockwise
A/C RAIN fully counterclockwise
TX on 12 nm
Table 3-5 video level
Check Point
TP5 on
SPU pcb
(trigger
at TP1) VR3
V
1 = 500 to 700 mV
V
2 = 4.2 0.2V
Rating Adjuster
25