Aiwa HS-RX490 - User Manual

Need help?

Do you have a question about the Aiwa HS-RX490 and is the answer not in the manual?

Overview

Function Description
Important Technical Specifications
Usage Features
Maintenance Features

This document provides a comprehensive service manual for the AIWA HS-RX490 stereo radio cassette player, available in AH and D models. It includes detailed specifications, block diagrams, schematic diagrams, exploded views, and parts lists to assist with maintenance and repair.

Function Description

The AIWA HS-RX490 is a portable stereo radio cassette player designed for listening to both radio broadcasts and cassette tapes. It features a built-in radio tuner for AM and FM bands and a cassette player with recording capabilities. The device is powered by either a rechargeable battery, dry cell batteries, or an optional AC adaptor, offering flexibility for portable and home use.

Important Technical Specifications

Frequency Range:

The radio tuner supports different frequency ranges depending on the reception area:

USA:
- AM: 530 – 1,710 kHz (10 kHz step)
- FM: 87.5 – 108.1 MHz (200 kHz step)
EU:
- AM: 531 – 1,602 kHz (9 kHz step)
- FM: 87.5 – 108 MHz (50 kHz step)
JPN:
- AM: 531 – 1,629 kHz (9 kHz step)
- FM: 76 – 108 MHz (100 kHz step in 76 – 90 MHz, 50 kHz step in 90 – 108 MHz)

Maximum Output:

The device delivers a maximum output of 4mW + 4mW (EIAJ/32Ω), ensuring clear stereo sound.

Power Sources:

The HS-RX490 offers versatile power options:

DC 1.2V using the supplied rechargeable battery NB-5G.
DC 1.5V using an R6 (size AA) dry cell battery.
AC house current using the optional AIWA AC-157 AC adaptor.

Battery Life (Approximate):

Battery life varies depending on the power source and function:

Tape Playback:
- NB-5G (fully charged): Approximately 9 hours
- R6 alkaline dry cell battery: Approximately 31 hours
- NB-5G and R6 alkaline dry cell battery combined: Approximately 40 hours
FM Reception:
- NB-5G (fully charged): Approximately 10 hours
- R6 alkaline dry cell battery: Approximately 33 hours
- NB-5G and R6 alkaline dry cell battery combined: Approximately 43 hours

Dimensions and Weight:

Maximum Dimensions: 109.6 (W) x 79.1 (H) x 24.6 (D) mm (4 3/8 x 3 1/8 x 31/32 in.)
Weight: Approximately 156g (5.5 oz) (excluding batteries)

Practical Service Figures:

These figures are crucial for performance evaluation and troubleshooting.

Radio Section:

Sensitivity (IHF, THD 3%):
- FM: Less than 17dB (at 87.5/98.5/108.0MHz for AH models; at 76.0/90.0/108.0MHz for D models)
- AM: Less than 57dB (at 630KHz), less than 56dB (at 999KHz), less than 55dB (at 1440KHz)
S/N 10dB:
- AM: 60dB ± 7dB (at 999kHz)
- FM: 15dB ± 8dB (at 98.5MHz for AH models; at 90MHz for D models)
Intermediate Frequency:
- FM: 10.7MHz ± 0.01MHz
- AM: 450kHz ± 7KHz
FM Stereo Separation: More than 23dB (at 98.5MHz for AH models; at 90MHz for D models)

Tape Section:

Tape Speed: 3015Hz ± 50Hz
Wow & Flutter: Less than 0.52% (RMS)
Take-up Torque: 20 ~ 30g-cm (FWD, REV)
F.F Torque: 70 ~ 150g-cm
Rew Torque: 70 ~ 150g-cm
Back Tension: 1 ~ 3g-cm (FWD, REV)
S/N Ratio: More than 43dB (PB, DC)
Distortion: Less than 3.0% (PB, DC)
Noise Level:
- Less than 3.0mV (Vol MAX, PB, DC)
- Less than 0.3mV (Vol MIN, PB, DC)
Frequency Response:
- 63Hz + 4/-6dB ~ 8kHz ± 4dB (NORMAL, PB)
- 63Hz + 2/-6dB ~ 8kHz + 4/-5dB (CrO2, PB)
Test Tape: TTA - 100, TTA - 210, TTA - 310 (CrO2), TTA - 320 (NORMAL)

Usage Features

The HS-RX490 is designed for ease of use with intuitive controls.

Radio Tuning: Features "UP/DOWN" buttons for tuning and a "MODE/SET/PHRASE" button for various radio functions.
Cassette Playback: Includes standard cassette player controls.
Hold Function: A "HOLD" switch prevents accidental operation.
Battery Indicator: An "OPE/BATT" indicator light shows the operational status and battery level.
Tape Selector: Allows selection between different tape types (e.g., Normal, CrO2).
DSL (Dynamic Super Loudness): Enhances bass and treble for a richer sound experience.
Preset Stations: Supports saving and recalling radio stations.
AMS (Automatic Music Sensor): Helps locate tracks on a cassette tape.

Maintenance Features

The service manual provides detailed information for troubleshooting, repair, and adjustment.

Block Diagrams: Illustrate the internal signal flow and interconnections of the ICs (TA2123AF, TK11823/TK11823MTL, TA2030FN, TA2022AFN), aiding in fault isolation.
Schematic Diagrams: Provide detailed circuit layouts with component values, essential for component-level repair.
Exploded Views and Parts Lists:
- Mechanical Exploded View 1/1: Shows the assembly of the main unit, including the chassis, lid, battery compartment, and control keys. Each part is numbered and listed with its part number, Kanri number, and description.
- Tape Mechanism Exploded View 1/1: Details the components of the tape mechanism, such as the head, pinch rollers, flywheels, gears, and springs. This is critical for servicing tape-related issues.
- Mechanical Parts List 1/1: Provides a comprehensive list of all mechanical components, including screws, springs, levers, and plastic parts, with their respective part numbers and descriptions.
- Tape Mechanism Parts List 1/1: Lists all parts specific to the tape mechanism.
- Accessories / Package List: Includes a list of standard accessories like the NB-5G battery, RB-107 charger, HP-M041 headphones, and RC490 remote control unit.
Spring Application Position: A dedicated diagram shows the correct placement of various springs within the tape mechanism, crucial for proper mechanical function.
Color Name Table: Standardized color codes for components are provided to ensure correct part identification.
Radio Section Adjustments:
- AM IF Adjustment (L253): For optimizing AM intermediate frequency.
- FM IF Adjustment (TC202): For optimizing FM intermediate frequency.
- AM VT Confirmation: Verifies voltage at TP4 (VT) at specific AM frequencies (531kHz and 1629kHz).
- FM VT Confirmation: Verifies voltage at TP4 (VT) at specific FM frequencies (76.0MHz and 108.0MHz).
- AM Tracking Adjustment (L251, TC251): For fine-tuning AM reception at 630kHz and 1440kHz.
- FM Tracking Adjustment (L201): For fine-tuning FM reception at 76.0MHz.
- FM VCO Adjustment (SFR251): Adjusts the Voltage Controlled Oscillator for FM at 76.0MHz to achieve a specific frequency counter reading (19kHz ± 100Hz at IC251 pin 12).
Tape Player Section Adjustments:
- Tape Speed Adjustment (SFR401): Uses a TTA-100 test tape and a frequency counter connected to the Phones Jack (J101) to adjust SFR401 for 3015Hz ± 10Hz (FWD) and ± 45Hz (REV). It also requires confirmation that wow and flutter are less than 0.50%.
IC Pin Descriptions: Detailed descriptions of each pin for the main ICs (e.g., TA2123AF) are provided, outlining their function (input/output, voltage levels, control signals), which is invaluable for circuit analysis and debugging.