Sanyo JA 224 Service Manual

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SERVICE MANUAL

POWER AMPLIFIER

JA 224

( EUROPE)

a on. v0

NOTE: SPEClFlCATIONS
The below mentioned specifications are mainly based on the lHF measurements standard.
They can therefore not directly be compared with specifications based on the DIN
standard or other standards.

Continous output power ............ 20 W x 2 (at 8 ohms, 0.9% distortion)
Input sensitivity and impedance
PHONO .................... 2.5mV/47 kohms
AUXvCD/TUNER/TAPE PLAY ..... 150 mV/47 kohms
Phono overload level ............... 130 mV RMS (at 1 kHz)
Output level
TAPE REC .................. 150 mV
Frequency response ............... 20 - 20,000 Hz (AUX-CD)
Tone control response
BASS ...................... :8 dB (at 100 Hz)
TREBLE .................... :8dBlat10kHz)
Loudness control response
100 Hz/lO kHz ............... +8 dB/+4 dB
Signal to noise ratio ............... 95 dB (AUX-CD)
Power requirements ............... AC: 220 V, 50 Hz
Power consumption ............... 100 W
AC output socket ................. AC: 18 V, 200 mA (max.l
Dimension (Approx.) .............. 420 (W) x 200 (D) x 80 (H) mm
(16-1/2 x 7-7/8" x 3-1/8")
Weight (Approx.) ................. 4 kg (9 lbs.)

* Specifications subject to change without notice.

WM<13267

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ADJUSTMENT

ADJUSTMENT OF B|AS

COND|TIONS

VOLUME Control : 0,, (Minimum) (-7
BALANCE Control ; "0,, (Center)
BASS Control : "0,, (Center) "in m:
TREBLE Control : 0,, (Center) U a gfié
FUNCTION SWitch 2 AUX-CD svmw man man swam:
SPEAKER Switch : "0N,,
SOUDNESS Switch : "OFF,,
MONITOR Switch : "SOURCE
Output Load : No Load

l'_1

After the power switch is turned on at 3 minutes, adjust SVR703 and SVR803 respectively as follows.
L - Channel: SVR703 for 1.0mV ~ l1.0mV reading between the both leads of R723.
R - Channel: SVR803 for 1.0mV ~ 4.0mV reading between the both leads of R823.

IC BLOCK DIAGRAM

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