Sony SRF-H3 Service manual

SRF-H3

SERVICE MANUAL

Ver 1.0 2000. 07

SPECIFICATIONS

Frequency range:

FM: 87.6 – 108 MHz AM: 530 – 1 710 kHz

Power output:

5.0 mW + 5.0 mW (at 10 % harmonic distortion)

Headphone type:

Dynamic

Power requirements:

1.5 V DC, one size AAA (R03) battery

Mass:

Approx. 132 g (4.7 oz) incl. a battery

Design and specifications are subject to change without notice.

Australian Model

FM STEREO/AM HEADPHONE RADIO

SECTION 1

GENERAL

This section is extracted from instruction manual.

Head band

Light reflector

FM flexible antenna

TUNE

Dial scale

SENS

Battery compartment

Driver units

AAA (R03) x 1

Support band

POWER

VOL

BAND

Getting Started

Installing the Battery

(See Fig.

1 2 3

When to replace the battery

Replace the battery when the sound becomes weak or distorted. Remove the old battery and insert a new one.

Battery life (approximate hours)

FM reception 80 40 AM reception 100 50

Notes on the battery

• Align the battery correctly.

• The dry battery cannot be charged.

• To avoid damage from possible battery

Wearing the Radio

1 2

While pressing the battery compartment lid, slide it to open. Insert one size AAA (R03) battery (not supplied) with correct polarity. To close the lid, press and slide the lid down until it clicks.

Sony Sony alkaline size AAA size AAA (R03) (LR03)

leakage, remove the battery when unit will not be used for a long time.

Pull out the support band fully from the headband. Adjust the headband and the support band to fit your head.

Insert the # side of the battery first.

SAFETY CHECK-OUT

After correcting the original service problem, perform the following safety checks before releasing the set to the customer.

1. Check the area of your repair for unsoldered or poorly-soldered connections. Check the entire board surface for solder splashes and bridges.

2. Check the interboard wiring to ensure that no wires are "pinched" or contact high-wattage resistors.

3. Look for unauthorized replacement parts, particularly transistors, that were installed during a previous repair . Point them out to the customer and recommend their replacement.

Note on the support band (See Fig. A)

When the radio not in use, put the support band back by pushing down both ends as illustrated and push it back underneath the headband.

Note on the light reflector (See Fig. A)

This reflector reflects a car light at night for your safety.

Playing the Radio

Set POWER to ON.

Set BAND to select FM or AM.

For FM, set SENS to LOCAL if interference is prevalent and reception is too strong. Under

normal condition, set it to DX.

Turn TUNE (tuning) to tune in a station.

Adjust the volume using VOL.

To turn off the radio

Set POWER to OFF.

4. Look for parts which, through functioning, show obvious signs of deterioration. Point them out to the customer and recommend their replacement.

5. Check the B+ voltage to see it is at the values specified.

6. Flexible Circuit Board Repairing

• Keep the temperature of the soldering iron around 270˚C during repairing.

• Do not touch the soldering iron on the same conductor of the circuit board (within 3 times).

• Be careful not to apply force on the conductor when soldering or unsoldering.

— 2 —

SECTION 2

DISASSEMBLY

Note : Follow the disassembly procedure in the numerical order given.

2-1. CABINET FRONT (R) ASSY

2 Cabinet front (R) assy

Claws

2-2. HOLDER (WITH DRIVER)

3 Holder

1 Unsolder two lead wires.

2-3. GEAR (TUNING) INSTALLATION

Cabinet rear (R) assy

Precision screwdriver

2 Push this

portion down.

Cabinet rear (R) assy

Model name (SRF-H3)

CV1

— 3 —

Gear (tuning)

1 Turn CV1 fully in the

direction of arrow.

Cabinet rear (R) assy

+ 7 hidden pages