Technics SAG 67 Service Manual

Page 1

ORDER NO. M09701 001 C1

Service Manual

AV Control Stereo Receiver

uri-

PRO-

. Specifications

I FM Tuner Section
Frequency range 87.9 - 107.9 MHz
Sensitivity 11.2 dBf (2 uV, IHF 58)
50 dB quieting sensitivity

MONO 18.3 dBf (4.5 uV, IHF 58)

STEREO 38.3 dBf (45 uV, IHF 58)
Total harmonic distortion

MONO 0.2%

STEREO 0.3%
SIN

MONO 75 dB

STEREO 70 dB
Frequency response 20 Hz - 15 kHz, +1 dB, -2 (13
Alternate channel selectivity 65 dB
Capture ratio 1 dB
Image rejection at 98 MHz 44 dB
IF rejection at 98 MHz 80 dB
Spurious response rejection at 98 MHz 75 dB
AM suppression 50 dB
Stereo separation

1 kHz 40 dB

10 kHz 30 dB
Carrier leak

19 kHz -35 dB

38 kHz -50 dB
Antenna terminal 75 Q (unbalanced)
I AM Tuner Section
Frequency range 530 - 1710 kHz
Sensitivity 20 pV, 330 uV/m
Selectivity 55 dB
Image rejection at 1000 kHz 40 dB
IF rejection at 1000 kHz 60 dB

Technics®

Receiver
L O G l C S] \- G 67
Colour
(K) . . . . . Black Type
Area fl
Suffix for
Model No. Area Colour

(PP) U.S.A. and Canada (K)

System No. : SOSSPC-K (Refer to page 3)

* Manufactured under license from Dolby
Laboratories Licensing Corporation. Additionally
licensed underone ormore ofthe following patents:
U.S. numbers 3,632,886, 3,746,792 and 3,959,590:
Canadian numbers 1,004,603 and 1,037,877.
"Dolby" and the double»D symbol are trademarks of
Dolby Laboratories Licensing Corporation.

I Video Section

Output voltage at 1 V input 110.1 Vp-p
Maximum input voltage 1.5 Vp-p
Input/output impedance 75 Q

I Amplifier Section
Rated minimum sine wave RMS power output

40 Hz - 20 kHz both channels driven

0.9% total harmonic distortion 70 W per channel (8 Q)
1 kHz continuous power output both channels driven

0.9% total harmonic distortion 73 W per channel (8 £2)
Total harmonic distortion

Rated power at 40 Hz - 20 kHz 0.9% (8 Q)

Half power at 1 kHz 007% (8 9)
Power output at the Dolby Pro Logic operation

0.9% at 1 kHz,

Front 2 x 70 W (8 9)

Center 70 W (8 £2)

Surround 70 W (8 Q)

(Surround speakers total impedance)

Low frequency damping factor 30 (8 0)
Load impedance

Front 8 0

Center 8 Q

Surround 4 - 8 Q
SMPTE intermodulation distortion 0.9%
Input sensitivity

PHONO 0.4 mV (3 mV, IHF 66)

CD, TAPE MONITOR, VCR , TVIDVD
27 mV (200 mV, IHF 66)
Input impedance
PHONO 47 k9
CD, TAPE MONITOR, VCR , TVIDVD 22 k9

© 1997 Matsushita Electronics (S) Pte. Ltd.
All rights reserved. Unauthorized copying and
distribution is a violation of law.

Contents

Page 2

SA-G67

information by anyone else could result in serious injury or death.

A WARNING
This service information is designed for experienced repair technicians only and is not designed for use by the general public. It does not contain
warnings orcautions to advise non-technical individuals of potential dangers in attempting to service a product. Products powered by electricity should
be serviced orrepaired only by experienced professional technicians. Any attempt to service or repairthe product orproductsdealt with in this service

SIN (IHF A)
PHONO
CD, TAPE MONITOR, VCR, TVIDVD

70 dB (73 dB, IHF 66)

75 dB (83 dB, IHF 66)
Frequency response
PHONO RIAA standard curve 10.8 dB
CD, TAPE MONITOR, VCR, TVIDVD
10 Hz- 60 kHz, :3 dB
Tone controls
BASS
TREBLE

50 HZ, +10 dB to 710d'B
20 kHz, +10 dB to -10dB

I Contents

I General
Power supply AC 120 V, 60 Hz
Power consumption 175 W

(In standby condition : 2W)
430 x158 X 309 mm

(16 5],5" X 57" X 125/32")
6.4 kg (14.2Ib,)

Dimensions (W x H x D)

Weight
Notes :
1. Specifications are subject to change without notice.

Weight and dimensions are approximate.
2, Total harmonic distortion is measured by the digital spectrum analyzer.

Page Page

SAFETY PRECAUTIONS ..................... 2 MEASUREMENTS AND ADJUSTMENTS ........................... 14
BEFORE REPAIRAND ADJUSTMENT 2 TERMINAL GUIDE OFIC's, TRANSISTORS AND DIODES. 14 ~15
PROTECTION CIRCUITRY. 2 SCHEMATIC DIAGRAM 15 ~ 25
LINE-UPOF COMPONENTS 3 BLOCK DIAGRAM ...... 26 ~ 29
FRONT PANELCONTROLS 3 PRINTEDCIRCUIT BOARD. . 30 ~ 35
OPERATION CHECKS & MAIN OOMPONENT REPLACEMENT 4 ~ 8 WIRING CONNECTION DIAGRAM 36
FAN MOTOR TROUBLESHOOTING 9 CABINETPARTS LOCATION. 87
TROUBLESHOOTING ........ REPLACEMENT PARTS LIST. . 38 ~ 40
TERMINALFUNCTION OFIC PACKAGING ........................ . 4o
RESISTORS&CAPACITORS. . 41 - 44

I Safety Precautions (This "Safety Precaution' is applied only "1 U S. A )

Before servicing. unplug the power cord to prevent an electric shock.

wewwd

. Insulation Resistance Test

1.
2. Turn on the power switch.
3

When replacing parts. use only manufacturers recommended components for safety.

Check the condition of me power cord. Replace if wear or damage is evident.

After servicing, be sure to restore the lead dress, insulation barriers, insulation papers, shields, etc.
Before returning the serviced equipment to the customer, be sure to make the following insulation
resistance test to prevent the customer from being exposed to a shock hazard.

Measure the resistance value with ohmmeter between thejumper AC plug and each exposed metal
cabinet part, such as screwheads, antenna. control shafts, handle brackets, etc. Equipmentwith antenna
terminals should read between 3M9 and 5.2MQ to all exposed parts. (Fig. 1 ) Equipment without
antenna terminals should read approximately infinity to all exposed parts. ( Fig. 2 )

Note : Some exposed parts may be isolated from the chassis by design. These will read infinity.

If the measurement is outside the specified limits, there is a possibility of a shock hazard. The equipment

should be repaired and rechecked before it is returned to the customer.

I Before Repair and Adjustment
Disconnect AC power, discharge both Power Supply Capacitors (0703 to C706) through a 1051 . 5W resistorto ground.
DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may destroy solid state devices.
After repairs are completed, restore power gradually using a variac, to avoid overcurrent.

Current consumption at 120V, 60 Hz in NO SIGNAL mode should be 400 ~ 1000 mA.

I Protection Circuitry

The protection circuitry may have operated if eitherof the following
conditions are noticed:

- No sound is heard when the poweris turned on.

0 Sound stops during a performance.
The function of this circuitry is to preventcircuitry damage if, for example,
the positive and negative speaker connection wires are 'shorted", or if
speakersystems with an impedance less than the indicated rated impedance
of the amplifier are used.

_2_

Anmnna
terminal \

Exposed
metal
part

Ohmmeter
Fig. 1

Resistance = aMQ - 5.2Mn

Unplug the power cord and short the two prongs of the plug with a jumper wire.

Exposed
metal
part

Ohmmeler
Fig. 2

Resistance = Approx 00

If this occurs, follow the procedure outlines below:
1.Tum off the power.
2. Determine the cause of the problem and correct it.
3. Turn on the power once again afterone minute.

Note:
When the protection circuitry functions, the unit will not operate unless
the power is first tumed off and then on again.