Technics SAAX 810 Service Manual

Page 1

ORDER NO. MD9707074C1
A2

Service Manual

Receiver

AV Control Stereo Receiver Uti-
SA-AX81O

PRO-LOGIC

Colour
(K) . . Black Type
Area
l
Suffix for
Model No, Area C°'°'
(P) U.S.A. (K)

* Manufactured underlicense from Dolby Laboratories Licensing Corpo-
ration. Additionally licensed under one or more of the following patents:
U.S. numbers 3,632,886,3,746,792and 3,959,590; Canadian numbers
1,004,603 and 1,037,877.

'Dolby" and the double-D symbol are trade marks of Dolby Laboratories

- - - Licensin Co oration.
I Specrflcatrons 9 'p
I FM Tuner Section I Amplifier Section
Frequency range 87.9 - 107.9MHz Rated minimum sine wave RMS power output
Sensitivity 11.2dBt (2W, IHF '58) 20 Hz-20 kHz both channels driven
50dB quieting Sensitivity _ 0.05% total harmonlc distortion 120W per channel (80)
MONO 18.3dBt (4.5uV, IHF 58) 1 kHz continuous power output,
STEREO 38.3dBf (45uV, IHF 58) both channels driven 0.05% total
Total harmonic distortion harmonic distortion 125W per channel (80)
MONO 0.2% Total harmonic distortion
STEREO 03% Rated power at 20 Hz - 20kHz 0.05% (89.)
SIN Half power at 1 kHz 0.03% (80)
MONO 75dB Power output at the Dolby Pro Logic operation
STEREO 70dB 0.9% at 1 kHz,
Frequency response 20Hz - 15kHz (+1 dB, -2dB) Front . 2X100 W (80)
Alternate channel selectivity 65dB Center 100 W (8;!)
Capture ratio 1dB Surround 2X100 W (89)
Image rejection at 98MHz 44dB Low frequency damping factor 30 (89)
IF rejection at QBMHz BOdB Load impedance
Spurious response rejection at 98MHz 75dB Front
AM suppression 50dB A or B 4-8:!
Stereo separation A and B 89
1 kHz 40dB Center 89
tokHz 30dB Surround 89
Carrier leak Dynamic headroom 2dB (80)
19kHz -35dB SMPTE intermodulation distortion 0,13%
38kHz ~50dB Frequency response
Antenna terminal(s) 7552 (unbalanced) PHONO RIAA standard curve i 08:13
CD, TAPE, TVNCR 2, VCl'1I 1, DVDIDSS
7H2 - 70kHZ, i 3dB
. Input sensitivity
I AM Tuner Section PHONO o,4mv (3mV, IHF '66)
Freqvencv range 530 - 1710kHZ co, TAPE, TVNCR 2, vcn 1, DVDIDSS
Sensitivty 20].l.V, 330uV/m 27mV (ZOOmV, [HF 66)
Selectivity 55dB SIM(IHF A)
Image rejection at toookHz 40dB pHoNo » 70dB (30,13, lHF 66)
IF reieelion a! 10°0kHz GOdB co, TAPE, TVNCR 2, vcn 1, DVD/DSS
75dB (85dB, IHF '66)
Input impedance
I Video Section PHONO 47kg
Output voltage at 1 V input (unbalanced) 1:0.1Vp-p Tonggolii-glEs TVNCR 2 VCR 1 DVDIDSS 22kg
Maximum input voltage 1.5Vp-p BASS 50Hz +10 to _ 1 0 dB
Input/output Impedance 750 TREBLE 20kHz: +10 to 40:13
Subwoofer frequency responce 7H2 - 100Hz, iSdB
Loudness control (volume at -30dB) 50Hz, +9dB

© 1997 Matsushita Electronics (S) Pte. Ltd.

. ® All rights reserved. Unauthorized copying and
ec I | 108 distribution is a violation of law.

Contents

Page 2

SA-AX810

,il. 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
wamings or cautions to advise non-technical individuals of potential dangers in attempting to service a product. Products powered by electricity should
be serviced or repaired only by experienced professional technicians. Any attempt to service or repair the product or products dealt with in this service
information by anyone else could result in serious injury or death.

I General Notes I
1, Specifications are subject to change without notice.

Power consumptlon 290W (In standby condition : 2W) Weight and dimensions are approximate.
power supply AC 120V, 60HZ 2. Total harmonic distortion is measured by the digital spectrum
Dimensions (w x H x D) 430 x 158 x 312 mm analyzer-

(ism/,5" x 67/3; x 129/32")
Weight 9.5kg (20.9Ib.)
I Contents

- SAFETY PRECAUTION ,,,,,,,,,,,,,,,,,,,,, 0 TERMINAL GUIDE OF ICs, TRANSISTORS & DIODES

0 BEFORE REPAIR AND ADJUSTMENT ° SCHEMATIC DIAGRAM ..............................................

- PROTECTION CIRCUITRY ......................................................... 2 0 PRINTED CIRCUIT BOARD ............................................ 37 ~ 43
. OPERATION CHECKS AND MAIN COMPONENT REPLACEMENT 3 ~ 7 ' WIRE CONNECTION DIAGRAM

t FAN MOTOR TROUBLESHOOTING .8 ' CABINET PARTS LOCATION

' TROUBLESHOOTING ................... 9 ~ 12 ' REPLACEMENT PARTS LIST

0 BLOCK DIAGRAM ............................................................. 13 ~ 17 ' RESISTORS & CAPACITORS ..........................

- TERMINAL FUNCTIONS OF ICs .............................................. 13 ' PACKAGING .....................................................

I Safety Precaution (This "Safety Precaution" is applied only in USA)

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

When replacing parts ,use only manufacturer's recommended components for safety . ermlna' :1 1

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

After servicing ,be sure to restore the lead dress, insulation barriers ,insulation papers ,shields ,etc . EXposed a

Before returning the serviced equipment to the customer, be sure to make the following insulation E? g
Ohmmetar

resistance test to prevent the customer from being exposed to a shock hazard .

def-9.?

Hesistanfig 1= 3MQ- 5.2MQ
. INSULATION RESISTANCE TEST

1. Unplug the power cord and short the two prongs of the plug with ajumper wire .

2. Turn on the power switch .

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

antenna terminals should read approximately infinity to all exposed parts . (Fig. 2 ) Exposed ,
*Note :Some exposed parts may be isolated from the chassis by design. These will read infinity . metal
4. If the measurement is outside the specified limits ,there is a possibility of a shock hazard .The equipment a
should be repaired and rechecked before it is returned to the customer , Ohmmeter

Fig. 2
Resistance = Approx co

I Before Repair and Adjustment

Disconnect AC power. discharge 4 Power Supply CapaCitors C703, C704, C705 and C706 through a 109 , 5W resistor to 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 AC 120 V, 60Hz in NO SIGNAL mode should be 500 ~ 1000 mA.

I Protection Circuitry

The protection circuitry may have operated if either of the follow- If this occurs, follow the procedure outlines below:
ing conditions are noticed: 1. Turn off the power.
- No sound is heard when the power is turned on. 2. Determine the cause of the problem and correct it.
0 Sound stops during a performance. 3. Turn on the power once again after one minute.
The function of this circuitry is to prevent circuitry damage if, for
example, the positive and negative speaker connection wires Note:
are "shorted", or if speakersystems with an impedance less than When the protection circuitry functions, the-unit will not operate
the indicated rated impedance of the amplifier are used. unless the power is first turned off and then on again.