Image

Description

Part

Value

Qty

Polyester capacitor (393K)

C32

39n

1

Polyester capacitor (2A183J)

C33

18n

1

Electrolytic capacitor

C29

47/16

1

Electrolytic capacitor

C31

1/50

1

NPN general purpose transistor

Q35

2SC828

1

1/4w Carbon resistor

R124

100R

1

1/4w Carbon resistor

R127

4K7

1

1/4w Carbon resistor

R128, R130

1M

2

1/4w Carbon resistor

R129

330K

1

1/4w Carbon resistor

R131

300K

1

1/4w Carbon resistor

R132, R133

22K

2

Trim potentiometer (P253)

TM4

25KB

1

Dual Operational Amplifier

U24

µPC4558C

1

Place and solder all resistors

Place TM4 , polyester capacitors and electrolytics capacitors. Solder them.

MAKE SURE ELCTROLYTIC CAPACITOR ARE IN THE RIGHT WAY

Test 4558 power . The red dot +15 V and green dot -15V (roughly 5%). Ground is on square pad of all potentiometers.

WARNING BEFORE POWER TEST ENSURE THAT FOUR WIRES ARE STILL CONNECT BETWEEN  IO BOARD AND MAIN BOARD

Solder the 4558 and the transistor. The silkscreen of the transistor Q35 is absent but the transistor that you see on the picture is Q35.

MAKE SURE THE 4558 AND Q35 ARE IN THE RIGHT WAY

Adjust the TM4 trimmer for  130mV on pin 1 of 4558.

To measure, use a voltmeter in AC mode (AC)

Here is the complete Noise you can go to  the Accent assembly