Panasonic sa pm 20 service manual

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ORDER NO, MD990202502

ervice Manual

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DIGITAS AUEDID mum-stage misc sir-pins
SBPMZO SA-PMZO SEPMZD

Remote Control
Transmitter

TAPE DECK . AR2 Mechanism Series
TRAVERSE DECK . RAE01522-M Mechanism Series

I Specifications
I AMPLIFIER SECTION

RMS power output
THD 10%, both channels driven
LOW 14 W per channel (69)
HIGH 6 W per channel (69)
Total Bl-AMP power 20 W per channel
input sensitivity
AUX 250 mV
input impedance
AUX 47 k9
Output impedance
Headphone 16 - 32 Q

I AM TUNER SECTION
Frequency range
Sensitivty SIN 20 dB

I FM TUNER SECTION

Frequency range 87.50 - 108.00 MHz (0.05 MHz steps)

Sensitivty 1.8 pV (IHF)
SIN 26 dB 15 (1V

Antenna terminal(s) 759 (unbalanced)

I CASSETTE DECK SECTION

522 - 1629 kHz (9 kHz steps)
500 uV/m

Track system 4 track, 2 channel
Heads
Record/playback Solid permalloy head
Erasure Double gap ferrite head
Motor DC servo motor

Recording system
Erasing system

AC bias 100 kHz
AC erase 100 kHz

CD Stereo System

SA- PM20

Colour
+!
I (S) , Silver Type
Area
Suffix for
Model No. Area C°'°'
(E) Europe
(EB) Great Britain (3)
(EG) Germany
System : SC-PM20
Main Unit SA-PMZD
Speakers SB-PM20
MASH is a trademark of NTT.
Tape speed 4.8 cm/s

Overall frequency response (-3,+3 dB at DECK OUT)

NORMAL (TYPE I) 50 Hz 713 kHz
HIGH (TYPE II) 50 Hz - 13 kHz
SIN 50 dB (A weighted)

Wow and flutter
Fast Ionivard and rewind times

018% (WRMS)
Approx. 120 seconds with 0-60
cassette tape

I CD SECTION
Sampling frequency
Decording

Beam source/wave length
Number of channels

44.1 kHZ

16 bit linear

Semiconductor laser / 780 nm
2 channel stereo

SIN

SP out 32 dB (JIS.A)
Wow and flutter Below measurable limit
Digital filter 8 f3
DA converter MASH (1 bit DAC)
I General
Power consumption * 62 W (Standby mode: 0.7 W)

Power supply [EIEG] AC 220-230 V, 50 Hz

[EB] AC 230-240 v, 50 Hz
Dimensions (W x H x D) 195 x 286 x 292 mm
Weight 50 kg

Notes :

11 Specifications are subject to change without notice.
Weight and dimensions are approximate.

2. Total harmonic distortion is measured by the digital spectrum
analyzer.

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 or cautions to advise non-technical individuals of potential dangers in attempting to sen/ice 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.

Panasonic®

© 1999 Matsushita Electronics (S) Pte. Ltd.
All rights reserved. Unauthorized copying
and distribution is a violation of law,

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SA-PM20

I Contents
PAGE PAGE

. ACCESSORIES ............................................................................. 2 BLOCK DIAGRAM ............................................................ 23 ~ 27
- BEFORE REPAIR AND ADJUSTMENT - SCHEMATIC DIAGRAM ..... 28 ~ 32
' PROTECTION CIRCUITRY ............... ° PRINTED CIRCUIT BOARD 33 ~ 39
- HANDLE PRECAUTIONS FOR TRAVERSE DECK ' WIRING CONNECTION DIAGRAM . 4O -- 41
' PRECAUTION OF LASER DIODE ....................... ° TROUBLESHOOTING GUIDE IIIIII 42
0 CAUTION FOR AC MAINS LEAD . MECHANISM PARTS LOCATION
- CONNECTIONS . ' LOADING UNIT PARTS LOCATION 44
- FRONT PANEL CONTRO 6 ' CABINET PARTS LOCATIONS 45 ~ 46
- LISTENING TO CD5 & RECORDING 7 ~ 10 ° REPLACEMENT PARTS LIST .. 47 ~ 50

014:0)me

' USING THE TIMER . 11 ~ 12 ' RESISTORS & CAPACITORS 51 ~ 54
' OPERATION CHECKS . . 13 ~ 18 ° PACKING MATERIALS & ACCESSORIES. 55
- TERMINAL GUIDE OF IC 5 TRANSISTORS AND DIODE ...... 19 ' PACKAGING ............................................................................... 55

- TERMINAL FUNCTION OF lC's., , 20 ~ 22

I Accessories

@

AC power cord VVVVV (for United Kingdom) AC power cord (for others) FM indoor antenna Batteries

iii

AM loop antenna set Antenna plug adaptor (tor United Kingdom) Remote control transmitter

I Before Repair and Adjustment

Disconnect AC power, discharge Power Supply Capacitor 6628 through a 109 , 10W 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 230V - 240V, 50 Hz in NO SIGNAL mode should be ~200mA.

I Protection Circuitry

The protection circuitry may have operated it either of the following conditions are noticed:
. No sound is heard when the power is turned on.
0 Sound stops during a performance.
The function of this circuitry is to prevent circuitry damage if, for example, the positive and negative speaker connection wires
are "shorted", or if speaker systems with an impedance less than the indicated rated impedance of the amplifier are used.
If this occurs, follow the procedure outlines below:

1. Turn off the power.
2. Determine the cause of the problem and correct it.
3. Turn on the power once again after one minute.

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