Technics SEA 1000 M 2 Service Manual

Page 1

ORDER NO. ADQTO709402

Service Manual

Stereo Power Amplifier

Specifications (DIN 45 500)

20 Hz - 20 kHz continuous power output

both channels driven 2 x70 W (8 Q)
1 kHz continuous power out put
both channels driven (THD: 1 %) 2x85 W (8 Q)

2 x 120 w (4 Q)
63 Hz - 12.5 kHz continuous power output

both channels driven (THD: 0.7 %) 2x 80 W (8 Q)
2 x 105 w (4 Q)
Total harmonic distortion (THD)
rated power at 20 Hz - 20 kHz 0.015 % (8 (I)
lntermodulation distortion I
(50 Hz: 7 kHz = 4: 1, SMPTE) 0.007 /5 (8 9)
Residual hum and noise 0.3 mV
Damping factor 70 (8 Q)
35 (4 Q)
Headphones output level/impedance 540 mV/330 9
Load impedance
Aor B,Bl-WlFthG 49-169
A and B 8 £2 - 16 9
input sensitivity/impedance
NORMAL, DIRECT 1 V/20 kn

(INPUT LEVEL CONTROL Max.)

SIN (rated power, 4 Q) 95 dB (110 dB, IHF 66)

SE-Ai 000W";

Colour
(K) ...... Black Type

Areas
(E) ........ Europe.
(EB) Great Britain.

(EG) Germany. '

Frequency response

NORMAL 5 Hz- 70 kHz (+0. --3 dB)
' (INPUT LEVEL CONTROL Max.)
+0 dB, -0.5 dB (20 Hz 4 20 kHz)
DIRECT 5 Hz- 70 kHz (+0, -3 dB)
+0 dB, -0.5 dB (20 Hz- 20 kHz)
I GENERAL

Power supply
For (E) and (EG) areas AC 50 Hz, 230 V
For (EB) area AC 50 Hz, 230 V - 240 V
Power consumption 280 W
Dimensions (W x H X D) 430 x 136 x344 mm
Weight 9.8 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.

AWARNING
This service iniormaticn 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 oi 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.

Technicsi

© 1997 Matsushita Electric industrial 00., Ltd.
All rights reserved. Unauthorized copying
and distribution is a violation of law.

Page 2

SE-A1000M2
I Contents

Before Repair ...'
Protection Circuitry
Accessories ....................
Caution for AC Mains Lead
Connections ......
Names of Parts.
Operations ........
Operation Check and

Main Component Replacement Procedures 8 - 11

I Before Repair

Measurements and Adjustments .
Schematic Diagram"
Printed Circuit Board Diagram
Type Illustration of 10s, Transistors an
Wiring Connection Diagram
Block Diagram ....................
Replacement Parts List (Electrical .
Replacement Parts List (Resistors and Capacrtors).
Cabinet Parts Location ..........................................
Replacement Parts List (Cabinet, Accessories and Packing)
Packaging .................................

(1)Turn off the power supply. Using a 10 Q, 10 W resistor, connect both ends of power supply capacitors (C701, C702) in order to

discharge the voltage.

(a) Before luming the newer eunpiu m1 AHA! nnmnlntinn nt rennir olnwlv anniy the primary vnltage by using a power supply voltage

controller to make sure that the consumed current at 50 Hz' In NO SIGNAL mode should be shown below with respect to supply

voltage 230 V/240 V.

Power supply voltage

AG 230 V, 50 Hz

AC 240 V, 50 Hz

Consumed current

160 mA - 320 mA

150 - 320 mA

I Protection Circuitry

The protection circuitry may have operated if either of the following conditions is noticed:

- No sound is heard when the power is switched ON.
- Sound stops during a performance.

The function oi this circuitry is to prevent circuitry damage it, 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 this unit are used. '

if this occurs, follow the procedure outlined below:
1,. Switch OFF the power.

2. Determine the cause of the cause of the problem and correct it.

3. Switch ON the power once again.

Note:

When the protection circuitry functions, the unit will not operate unless the power is first switched OFF and then ON again.

I Accessories

0 AC power supply cord
(E) and (EG) areas: (RJAODtQ-ZK} 1

- Connection cable for remote control
(SJPZZSTT) .......................................... 1

tit

Page 6

SE-A1000M2

I Name of Parts

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POWER METER LIGHT

® Power ".I. STANDBY (I) .-. ON" switch
(POWER, .1 STANDBY d) .- ON)
Press to switch the unit trom on to standby mode or vice versa.
In standby mode. the unit is still consuming a small amount of
power.

® Remote standby indicator (REMOTE STANDBY)
When the unit is connected to the AC mains supply, this indica-
tor lights up in standby mode and goes out when the unit is
turned on.

© Operation indicator (OPERATION)
This indicator illuminates when the power amplifier is in the nor-
mal operating condition.
lithe (-1-) and H wires of the speaker cables are shorted, or it a
circuit abnormality such as DC voltage in the power output to the
speakers is detected, the protection circuit will operate and the
"OPERATION indicator will turn off.

(9 Headphones jack (PHONES)

® Power meters
Indicate the output (watts) of this unit.
When speakers having an impedance at B Q are connected. the
output level will be as indicated. However, if the speaker Imped-
ance is 16 Q, the output level will be one-half the indicated
value, and if the impedance is 4 Q, the output level will be dou-
ble the indicated value.

Actual - meter
output - indication

8 (Q)
impedance of the speakers (9)

The power meter lights are turned on by pressing the POWER
METER LIGHT button on the amplifier rear.

© Speaker select buttons/indicators (SPEAKERS)

Q) Cooling fan
The cooling fan operates at high power output levels only.

It