Akai AM 1020 Service Manual

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SECTION 1

SERVICE MANUAL

TAB LE OF CONTENTS

I. SPECIFICATIONS .................................................................. 2
II. DISMANTLING 0F UNIT ............................................................ 4
III. ARRANGEMENT 0F PRINCIPAL PARTS ............................................... 5
IV. FM TUNER SECTION ADJUSTMENTS ................................................. 6
V. AM TUNER SECTION ADJUSTMENT (Model AA-1020) ................................... 10
VI. AM (LW AND MW) TUNER SECTION ADJUSTMENT (Model AA-1020L) ..................... ll
1. LW SECTION ADJUSTMENT ....................................................... II
2. MW SECTION ADJUSTMENT ....................................................... 11
VIII MAIN AMPLIFIER ADJUSTMENT ..................................................... 12
VIII. TUNflIG CORD THREADING ......................................................... 13
IX. CLASSIFICATION OF VARIOUS P.C BOARDS .......................................... I4
1 PC BOARD INTERCHANGEABILITY CHART ........................................ l4
2 COMPOSITION OF VARIOUS P.C BOARDS ........................................... 15

F01 basic adjustments, measunng methods, and operating principles, refer to GENERAL OPERAT-
ING PRINCIPLES AND ADJUSTMENTS.

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I. SPECIFICATIONS

An asterisk next to a figure indicates the minimum guaranteed performance.

1. AMPLIFIER SECTION (Models AA-lO20 and AA-IOZOL)

RATED OUTPUT

20 watts per channel (both channels driven). Minimum RMS, at 8 ohms load
impedance from 20 to 20,000 Hz, with on more than 0.4% total harmonic
distortion.

POWER BAND WIDTH (IHF)

10 to 60 kHz at 8 ohms, distortion within 0.4%.

INPUT SENSITIVITY PHONO-l, 2 3 mV/50 k Ohms (~48 :15 dBm) with Output 24.3 dBm, 8 ohms as standard.
TAPE-l, 2 150 mV/80 k ohms (-14 :1.5 dBm) with output 243 dBm, 8 ohms as standard.
AUX 150 mV/80 k ohms (714 21.5 dBm) with output 243 dBm, 8 ohms as standard.
ESIDUAL NOISE Less than 1.4 mV (Less than A55 dBm)
SIGNAL TO NOISE RATIO PHONO-l, 2 Better than 80 dB (Less than 740 dBm, input shorted)
(IHF) TAPE-1. 2 Better than 90 dB (Less than -50 dBm, input open)
AUX 1 Better than 90 dB (Less than 750 dBm, input shunted at 5 k Ohms)
TONE CONTROL BASS 1 10 :1.5 dB, -10 :15 dB at 100 HZ
TREBLE 1 10 :1.5 dB, -10 :1.5 dB at 10 kHz
SSWNTROL 1 10 :1.57dBflart 100 Hi 7 '
- 7 "fl, 6:1,5dBat10kHz 7 7 7 7
FILTER LOW CUT -6 dB at 50 Hz *-8 11.5 dB at 50 Hz
,,,,, HIGH CUT -9 dB at 10 kHz *-9:1.5 dB at 10 kHz
FREQUENCY RESPONSE (PHONO) RIAA :1 dB 7 ' ' " 7 V V '

EI-IANNEL SEARATION (II-171577
CTROSS @161??qung 7 '7
L-R gEyIATIONtPPIONO)

RECORDING'OUTPUfiPHONO) PIN
DIN

*13.11:1.0 dB at 100 HZ
*713.75 11.0 dB at 10 kHz

Better than 55 dB at 1,000 HZ
*Better than 50 dB at IOOQUZW:
Better than7507dB , ,

Within 341; V , 7'" ' ' T" 7' 7
150TI1V(714.3 :2 dBm)
26 mV (428.2 :2 dBm)

2. FM TUNER SECTION (Models AA-1020 and AA-IOZOL)

F REQUENCY RANGE

88 to 108 MHz
*87.4 to 109 :1 MHz

DIAL TRACKING ERROR :250 kHz
SENSITIVITY (IHF) 1 2.0 V

*Less than 3.2 IN (10 dB)
SENSITIVITY DEVIATION 1 Within 3 dB

IMAGE REJECTION RATIO

IF REJECTION RATIO

Better than 65 dB at 98 MHZ
*Better than 50 dB (IHF)
Better than 90 dB at 98 MHz
*Better than 80 dB (IHF)

CAPTURE RATIO (IHF) Less than 2 dB

LIMITING SENSITIVITY Less than 8 dB (Audio output 71 dB)
MUTING SENSITIVITY 1 15 to 30 dB

SELECTIVITY (IHF) Better than 70 dB

7 *Better than 65 dB

AM SUPPRESSION RATIO Better than 45 dB

SIGNAL TO NOISE RATIO

Better than 68 dB
*Better than 50 dB (STEREO) including carrier leak
*Better than 60 dB (MONO)

DISTORTION FACTOR

FREQUENEY RESPONSE "

Less than 0.5% (STEREO)
*Less than 1.0% (STEREO)
Less than 0.3% (MONO)
*Less than 0.5% (MONO)
-13 :I dBTAtWTHz (US-A)
710.5 :1 dB at 10 kHz (US-B)

STEREO SENSITIVITY 4.5 av (15 :3 dB) 7
EEO SEPAIJTIONWT Better than 40 dB

L-R DEVIATION 7 T Within 3 dB

RECORDING OUTPUT " PIN 390 mV (-6 :3 dBm)

DIN

70 mV (-21 :3 dBm)