Sony CA-755 Maintenance Manual page 40

2-4. TR-101 Board Adjustment
2-4-9. CHU INCOM Level Adjustment
2-4-10. CCU INCOM Demoduration Level Adjustment
2-4-9. CHU INCOM Level Adjustment
Preparations :
. Connect the CA-755/755P to a completely-adjusted CCU.
. S1/TR-101 board → DYNAMIC
. S2/TR-101 board → NORMAL
. Supply an 1 kHz, 2.2 mV p-p (_60 dBu) sine wave from
the low frequency oscillator to Pin 1 (Y), Pin 2 (X) and
Pin 3 (G) of INCOM/PGM connector of the CA-755/
755P.
. ENG/PROD switch (CA-755/755P) → PROD
Equipment : Oscilloscope/Audio level meter
Low frequency oscillator
Test point : Pin 4 (X), Pin 3 (G)/
INCOM connector(CA-755/755P)
Adjustment point : 1RV5 (INCOM DEV)/
TR-101 board
: 0 ± 0.2 dBu
Specifications
9 8 7 6
A
TP6
TP7
B
RV11
C
RV14
D
TP10
RV16
TP15
E
E2
TP14
F
RV15
TP11 LV6
G
TP12
H LV8
TP8
LV7
J
RV5
TP4
K
LV4
RV4
L
LV3
TP1
M
RV2
RV12
N
TR-101 BOARD (A SIDE)
2-14 (E)
5 4 3 2 1
RV6
RV9
RV8 RV3
TP13
CN1
TP9
TP16
LV5
E1
TP2
TP5
LV1
TP3
LV2
RV1
2-4-10. CCU INCOM Demoduration Level
Adjustment
Preparations :
. Connect the CA-755/755P to a completely-adjusted CCU.
. Supply an 1 kHz, 2.2 V p-p (0 dBu) sine wave from the
low frequency oscillator to Pin 1 (Y), Pin 2 (X) and Pin
3 (G) of INTERCOM connector on the CCU front panel.
. Setting of the CCU switches
(CCU-550 series)
S601(INCOM PROD SELECT)/AU-231 board → 4W
S602(INCOM ENG SELECT)/AU-231 board → 4W
(CCU-700/700A series)
S2062(PROD/PRIVATE/ENG)/AT-88 board → PROD
S2241(INCOM PROD SEL)/AT-88 board → 4W
To be extended : TR-101 board
Equipment : Oscilloscope/Audio level meter
Low frequency oscillator
Test point : TP15/TR-101 board
Adjustment point : 1RV16 (INCOM LEVEL)/
TR-101 board
: 220 ± 10 mV p-p (_20.0 ± 0.2 dBu)
Specifications
Setting after adjustment
. Reset each switch to the former position.
CA-755/755P