Panasonic SA AK20

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ORDER NO. MD970302502

Service Manual

@CDMPACT

MASH"1

mullx stage noise shaping

DIGITAL AUDIO

SB-AK20

SA-AK20

Remote Control
Transmitter

*2 Dolby noise reduction manufactured under license from
Dolby Laboratories Licensing Corporation.

"Dolby" and the double-D symbol are trade marks of Dolby
Laboratories Licensing Corporation.

TAPE SECTION : AR2 MECHANISM SERIES

Dflm

CD Stereo System

SA- AK20

Colour
(K) Black Type

Area
Suffix for
Model No. Area Colour
(E) Europe
(EB) Great Britain (K)
(EG) Germany and Italy
*1 MASH Is a trademark of NTT.
System Music Center Speaker
SC-AK20 (E) SA-AK20 (E)
SC-AK20 (EB) SA-AK20 (EB) SB-AK20 (E)
SC-AK20 (EG) SA-AK20 (EG)

CD SECTION : RAE015OZ TRAVERSE DECK SERIES

I Specifications

I Amplifier Section
1 kHz continuous power output
Both channels driven 2 x 35W (THD 1%, 6 Q)
RMS 2 x sow (THD 10%, e a)
Total harmonic distortion

Half power at 1 kHz 0.09% (69)
Frequency response

AUX 6on - 20kH2(-3db)
Input sensitivity and impedance

AUX 250mV,22K§1
Tone controls

6 E0 SPACE HEAVY,CLEAR,SOFI',DISCO,LIVE,HALL
V.BASS (volume at -30dB) 63Hz, 7dB
Load Impedance 69
I FM Tuner Section
Frequency range 87.5 - 108.0 MHz
Sensitivity 23.3 dBi
Total harmonic distortion

MONO 0.3%

STEREO ' 0.5%
SIN

MONO GOdB

Antenna terminaKs) 75 Q (unbalanced)

Panasonici

I AM Tuner Section

Frequency range

Sensitivity (for 50mW, 500mW)
MW(at 999kHz, 1000kHz)

522 - 1611 kHz

250 uV/rn

I Cassette Deck Section

Track system 4 track, 2 channel

Heads
Record/playback Solid permalloy head(Roiary head)
Erasure Double gap ferrite head

Motor DC servo motor
Recording system AC bias 100 kHz

Erasing system AC erase 100 kHz
Tape speed 4.8 cm/s
Frequency response
NORMAL 35 Hz - 14 kHz(+3dB,-6dB)
HIGH 35 Hz - 14 kHz(+3dB,-6dB)
SIN (HIGH)
Dolby NR off 50 dB (A weighted)
Dolby NR on 60 dB (CCIR)

Wow and flutter
Fast forward and rewind time
Approx. 120 seconds with C-60 cassette tape

0.1a % (WRMS)

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

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SA-AKM

by anyone else could result in serious injury or death.

[It WARNIN G
This service Information is designed for experiense repairtechnicians only and is not designed for use by the general public. it does not contain warnings
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 p rofessional technicians. Any attempt to service or repair the product or products dealt with in this se Nice information

I CD Section

Sampling frequency 44.1 kHz
Decoding 16 bit linear
Beam source/wave length Semiconductor Iaser/ 780 nm
Number of channels Stereo

Frequency response 20Hz H 20kHz (+1 dB, -2dB)
SIN

CD LINIT OUT 95 dB (JIS. A)

SP OUT 87 dB (JIS. A)
Wow and flutter Below measurable limit
Digital filter 8 ts
DIA converter MASH (1 bit DAC)
l Contents Page
HANDLING PRECAUTIONS FOR TRAVERSE DECK 2
PRECAUTION OF LASER DIODE 3
CAUTION FOR AC MAINS LEAD .. 4
BEFORE REPAIR AND ADJUSTMENT 5

BEFORE MOVING OR SHIPPING THIS UNIT . . 5
OPERATION CHECKS AND MAIN COMPONENT REPLACEMENT
SELF-DIAGNOSTIC DISPLAY FUNCTION
CD TEST MODE FUNCTION .................
MEASUREMENTS AND ADJUSTMENTS
TERMINAL FUNCTION OF ICS
WIRING CONNECTION DIAGRAM
TERMINAL GUIDE OF ICs, TRANSISTORS AND DIODE
BLOCK DIAGRAM ......................................................... 21 ~ 27

I General
Power consumption 120W
Power supply
for E, E6 AC 230 V, 50 HZ
for EB AC 230 -- 240V, 50 HZ
Dimensions (W x H x D) 270 x 380 x 314 mm
Weight 7.6 kg
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.

PRINTED CIRCUIT BOARD
SCHEMATIC DIAGRAM ..
TROUBLESHOOTING GU
MECHANISM PARTS LOCATION (RAA3405)
MECHANISM PARTS LIST ..............

LOADING MECHANISM PARTS LIST 54
CD LOADING UNIT PARTS LOCATION . 55
CABINET PARTS LOCATION .. 6 & 57
REPLACEMENT PARTS LIST 8 ~ 61
RESISTORS & CAPACITORS .. 1 ~ 65
PACKING MATERIALS & ACCESSORIES . 66
PACKAGING ........................................ 67

I Handling Precautions For Traverse Deck

The laser diode in the traverse deck (optical pickup) may break down due to potential difference

caused by static electricity of clothes or human body.

So, be careful of electrostatic breakdown during repair of the traverse deck (optical pickup).

- Handling of traverse deck (optical pickup)

1. Do not subject the traverse deck (optical pickup) to static
electricity as it Ie extremely sensitive to electrical shock.

2. To prevent the breakdown of the laser diode, an antistatic
shorting pin is inserted into the flexible board (FPC board).
When removing or connecting the short pin, finish the job
in as short time as possible.

3. Take care not to apply excessive stress to the flexible board
(FPC board).

4. Do not turn the variable resistor (laser power adjustment). It
has already been adjusted.

- Grounding for electrostatic breakdown prevention

_t

. Human body grounding
Use the anti-static wrist strap to discharge the static
electricity irom your body.
2. Work table grounding
Put a conductive material (sheet) or steel sheet on the
area where the traverse deck (optical pickup) is placed,
and ground the sheet.

Caution :

The static electricity of your clothes will not be grounded
through the wrist strap. So, take care not to let your
clothes touch the traverse deck (optical pickup).

Variable resistor
(Do not turn)

/, Optical pickup
:Ect' " Le 5 (Do not touch)

FPC
(Handle it carefully)

Eli?" Snorting pin
3 E; 5 91 i
I w z I I
hum - ------- I

Be sure to short this portion
(Use the shorting pin or clip)

1MB

Iron plate or some metals
to conduct electricity