SONY MDRRF945R
Manual de Servicio

MDR-RF915R/RF945R

TABLE OF CONTENTS
Specifications ............................................................................ 1 3-5. Free Run Frequency Check and Adjustment (MRD-RF945R) ......... 6 3-6. Receive Frequency Check and Adjustment (MRD-RF945R) ......... 6 3-7. Carrier Modulation Check (MRD-RF945R) ............... 6 3-8. Separation Check (MRD-RF945R) ............................. 6

1. GENERAL ....................................................................... 2 2. DISASSEMBLY
2-1. RX-BASE Board ...................................................... 3

3. ELECTRICAL ADJUSTMENTS .............................. 4
3-1. Free Run Frequency Check and Adjustment (MRD-RF915R) ....... 5 3-2. Receive Frequency Check and Adjustment (MRD-RF915R) ....... 5 3-3. Carrier Modulation Check (MRD-RF915R) ............. 5 3-4. Separation Check (MRD-RF915R) ........................... 5

4. DIAGRAMS
4-1. Block Diagrams ........................................................... 8 4-2. Schematic Diagram ..................................................... 9 4-3. Printed Wiring Board ................................................. 10

5. EXPLODED VIEWS........................................................11 6. ELECTRICAL PARTS LIST........................................12

SECTION 1 GENERAL

This section is extracted from instruction manual.

5- A Turn up the volume to a moderate
level with the VOL control. Press the TUNING button briefly for automatic tuning of the headphones. If you do not receive a clear audio signal, press it again.
Auto power on/off function When you remove the headphones from your head, the power turns off automatically. Do not allow the self adjusting band to be pulled up, otherwise the headphones will be switched on.

A MDR-RF945RK

TUNING button VOL control

The power turns on.

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

5- B Turn up the volume to a moderate
level with the VOL control, then tune the headphones in to the frequency of the transmitter with the TUNING control until you can hear the audio signal loud and clear.

1. 2. 3.

Check the area of your repair for unsoldered or poorly-sol deredconnections. Check the entire board surface for solder splashes and bridges. Check the interboard wiring to ensure that no wires are �pinched� or contact high-wattage resistors. Look for unauthorized replacement parts, particularlyt ransis

BMDR-RF915RK

TUNING control VOL control

Try the above steps 3 and 5 until the receiving performance becomes better.

tors, that were installed during a previous repair. Point them out to the customer and recommend their replacement. 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

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