background image

DC IN 9V

OFF ON

FILTER

NOISE

1 2 3

CHANNEL

R

B

A

L

AUDIO IN

DC IN 9V

OFF ON

FILTER

NOISE

1 2 3

CHANNEL

R

B

A

L

AUDIO IN

RECYCLING NICKEL-CADMIUM BATTERIES

Nickel-Cadmium batteries
are recyclable. You can help
preserve our environment by
returning your unwanted
batteries to your nearest
point for collection, recycling
or proper disposal.

Note: In some areas the disposal of nickel-

cadmium batteries in household or
business trash may be prohibited.

RBRC (Rechargeable Battery Recycling
Corporation) advises you about spent battery
collection by the following phone number.

Call toll free number: 1-800-822-8837 (United
States and Canada only)

Caution: Do not handle damaged or leaking
nickel-cadmium batteries.

To recharge the headphone battery after
use

Since little electric current is used for charging,
there is no need to worry about overcharging.

Charging and using hours

* at 1 kHz, 1 mW + 1 mW output
** The hours required to fully charge empty battery

N

 Operating the system

Listening to a program
1

First turn on the audio/video equipment
and start playing.

2

Remove the headphones from the
transmitter.
The transmitter’s power indicator will
light in red.

3

Select the radio frequency with the
CHANNEL selector.

4

When you put on the headphones the
headphone power turns on
automatically.

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.

A

 MDR-RF945RK

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.

B

 MDR-RF915RK

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

C

To connect to TV, etc.
If noise occurs when the transmitter is
connected to the headphone jack of your
TV or VCR, set the NOISE FILTER switch
to ON.

Notes

• If you connect the transmitter to LINE OUT or REC

OUT jack, do not set the NOISE FILTER switch to
ON. Otherwise, the volume will be limited.

• The NOISE FILTER switch effects the sound only in

cases such as connection diagram 

C

. In diagrams 

A

and 

B

, the switch has no effect.

• When the transmitter is placed on or near a TV, it

may pick up a noise. In such case, place the
transmitter away from the TV.

2

Connect the transmitter to an AC outlet
using the supplied AC power adaptor.

Notes

• Use only the supplied AC power adaptor. Do not use

any other AC power adaptor.

Polarity of the plug

• When you connect the connecting cord directly to an

earphone jack, the audio signal will not be output
through the right channel. In such a case, use the
separately sold PC-236HG plug adaptor.

• If the connected equipment has the AVLS (Automatic

Volume Limiter System) function, be sure to turn the
function off when using the transmitter. Otherwise, you
will have to turn up the volume of the headphones, and
that may cause noise.

• Do not place the transmitter near a fluorescent lamp, etc.

when using the system.

* WALKMAN is a registered trademark of Sony

Corporation.

Charging the
headphone battery

Using the headphones for the first
time

When you use the headphones for the first time,
charge the battery in the following manner.

1

Connect the transmitter to a power
source.

2

Place the headphones on the transmitter.

Place the headphone on the transmitter such that
the charging pins on the transmitter engage the
charging contacts on the bottom of the right-hand
housing.
The charge indicator on the transmitter will light
in green to indicate that the battery is being
charged.

Setting up the
transmitter
1

Connect the transmitter to audio/video
equipment. Select one of the hookups
below depending on the jack type:

A

To connect to a headphones jack

B

To connect to LINE OUT or REC OUT
jacks

DC IN 9V

OFF ON

FILTER

NOISE

1 2 3

CHANNEL

R

B

A

L

AUDIO IN

Operating Instructions

Mode d’emploi

Wireless Stereo
Headphone System

Sony Corporation © 2001   

Printed in Korea

MDR-RF945RK
MDR-RF915RK

3-233-607-21(1)

Sending RF signals from the Transmitter

The transmitter starts sending the RF signals
automatically, when it detects audio signals from
the equipment connected.
If it does not detect an audio signal for more than
approximately four minutes, the transmitter will
stop sending RF signals, and the power indicator
turns off.
When the transmitter receives an audio signal
again, it starts sending the RF signals, and the
power indicator will light in red again.
If the audio signal is very weak, the transmitter
does not send RF signals. If the transmitter is
connected to a headphone jack, make sure the
volume of the equipment connected is set to 5 – 6
or higher.
You may not hear the beginning of the sound from
the headphones until the transmitter starts sending
the RF signals after detecting an audio signal.

Note

If the transmitter is connected to the headphones jack of
the source equipment, set the volume of that equipment
as high as possible without distorting the audio signal.

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.

 The power turns on.

Note

If a hissing noise is heard move closer to the transmitter.

After listening to a program

Take the headphones off and rest them away on
the transmitter, and recharge them.

Note

Do not hang the headphones by the self adjusting band,
otherwise, the self adjusting band will be pulled up and
the headphones will be switched on.

The effective areas of
the transmitter

The optimum distance is up to approximately 150
feet (46 m) without the system picking up some
interference. However, the distance may vary
according to the surroundings and environment. If
the system picks up some noise while using it
within the above mentioned distance, reduce the
distance between the transmitter unit and the
headphones, or select the other channel.

Notes

• When you use the headphones inside the effective areas

of the transmitter, the transmitter can be placed in any
direction from the listener.

• Even within the signal reception area, there are some

spots (dead spot) where the RF signal can not be
received. This is a characteristic inherent to RF signals,
and does not indicate malfunction. By slightly moving
the transmitter, location of the dead spot can be
changed.

Transmitter

Left channel
(white)

Right channel
(red)

Unimatch plug
adaptor
(supplied)

Discman, MD,
WALKMAN*, VCR,
etc.

to headphones
jack (stereo
mini jack)

Connecting cord
(supplied)

to AUDIO IN
A jacks

to headphones
jack (stereo
phone jack)

TV, etc.

to stereo mini jack

Transmitter

to AUDIO IN
A jack

Left channel
(white)

Right channel
(red)

Connecting cord
(supplied)

Transmitter

to AUDIO IN
B jack

Connecting cord
(supplied)

Right channel
(red)

Left channel
(white)

to LINE OUT or REC
OUT jacks

Stereo system, VCR, etc.

No sound/Muffled sound

,

Turn on the transmitter first, then put on the
headphones.

,

Check the connection of the audio/video
equipment or the AC power adaptor.

,

Check that the audio/video equipment is turned
on.

,

Turn up the volume on the connected audio/
video equipment, if the transmitter is connected
to the headphones jack.

,

MDR-RF915RK:
Change the radio frequency with the CHANNEL
selector on the transmitter, then tune the
headphones with the TUNING control.
MDR-RF945RK:
Change the radio frequency with the CHANNEL
selector on the transmitter, then press the
TUNING button again.

,

The mute function is activated.
Use the headphones near the transmitter.

,

The headphones’ POWER indicator light is weak
or turned off.
• Charge the built-in rechargeable battery or if the

POWER indicator is still off after charging the
built-in rechargeable battery, take the
headphones to a Sony dealer for replacement of
the rechargeable battery.

,

If you connect the transmitter to the LINE OUT or
REC OUT jack of an audio reproducer, make sure
that the NOISE FILTER switch is set to OFF.

,

Make sure that the NOISE FILTER switch is set to
either ON or OFF (If the switch gets stuck
between ON and OFF, the sound will be cut off).

Distortion

,

If the transmitter is connected to the headphones
jack, turn down the volume of the connected
audio/video equipment.

,

Change the radio frequency with the CHANNEL
selector on the transmitter.

,

The headphones’ POWER indicator light is weak
or turned off.
• Charge the built-in rechargeable battery or if the

POWER indicator is still off after charging the
built-in rechargeable battery, take the
headphones to a Sony dealer for replacement of
the rechargeable battery.

,

If you connect the transmitter to LINE OUT or
REC OUT jack of an audio reproducer, make sure
that the NOISE FILTER switch is set to OFF.

Loud background noise

,

Move closer to the transmitter. As you move
away from the transmitter, more noise is likely to
be heard.

,

If the transmitter is connected to the headphones
jack, turn up the volume of the connected audio/
video equipment.

,

MDR-RF915RK:
Change the radio frequency with the CHANNEL
selector on the transmitter, then tune the
headphones with the TUNING control.
MDR-RF945RK:
Change the radio frequency with the CHANNEL
selector on the transmitter, then press the
TUNING button again.

,

The headphones’ POWER indicator light is weak
or turned off.
• Charge the built-in rechargeable battery or if the

POWER indicator is still off after charging the
built-in rechargeable battery, take the
headphone to a Sony dealer for replacement of
the rechargeable battery.

,

If you connect the transmitter to the LINE OUT or
REC OUT jack of an audio reproducer, make sure
that the NOISE FILTER switch is set to OFF.

Specifications

General

Carrier frequency

913.5 – 914.5 MHz

Channel

Ch1, Ch2, Ch3

Modulation

FM stereo

Frequency response

20 – 20,000 Hz

Transmitter TMR-RF945R, TMR-RF915R

Power source

DC 9 V: supplied AC power adaptor

Audio input

phono jacks/stereo mini jack

Dimensions

Approx. 150 mm dia. 

×

 108 mm

(6 

×

 4 

1

/

3

 in.) (w/h)

Mass

Approx. 190 g (6.7 oz.)

Headphones MDR-RF945R, MDR-RF915R

Power source

DC 2.4 V: Built-in rechargeable

battery

Mass

Approx. 240 g (8.5 oz.) incl.
built-in rechargeable battery

Built-in Ni-Cd rechargeable battery

Model name

NC-AA

Voltage

1.2 V

Capacity

700 mAh

Optional accessory

Plug adaptor

PC-236HG (stereo mini jack 

y

monaural mini plug)

Design and specifications are subject to change without
notice.

Troubleshooting

Welcome!

Thank you for purchasing the Sony
MDR-RF945RK/RF915RK Wireless Stereo
Headphone System. Before operating the unit,
please read this manual thoroughly and retain it
for future reference.
Some features are:
• Wireless system that allows you to listen to a

program free from the restriction of a cord

• High fidelity sound reproduction
• A compact transmitter with an AC power

adaptor (supplied) enables simple charging of
the headphone battery. Just by placing the
headphones on the transmitter, headphone
battery can be charged.

• Comfortable Supra-aural headphones with self

adjusting head band

• Automatic ON/OFF function on headphones to

preserve battery power

Notes on receiving
performance

The system for this equipment utilizes very high
frequency signals in the 900 MHz band so the
receiving performance may deteriorate due to the
surroundings. The following examples illustrate
conditions that may reduce the possible receiving
range or cause interference with reception.
• Inside a building with walls containing steel

beams.

• Area with many steel file cabinets, etc.
• Area with many electrical appliances capable of

generating electromagnetic noise.

• Transmitter is placed on a metal instrument.
• Area facing roadways.
• Noise or interfering signals exist in the

surroundings due to radio transceivers in trucks,
etc.

• Noise or interfering signals exist in the

surroundings due to wireless communication
systems installed along roadways.

to an AC outlet

To DC IN
9 V jack

AC power adaptor
(supplied)

Transmitter

1 2 3

CHANNEL

TUNING
button

VOL control

Replacing the ear
pads

When the ear pads become dirty or damaged, you
can get replacements from your Sony dealer.
Replace them as illustrated below.

1

Remove the old ear pad by pulling it out
of the groove on the housing.

2

Place the new ear pad on the driver unit
and insert the edge of the pad into the
groove as illustrated.

Make sure that the entire edge of the ear pad is
securely inserted into the groove.

N

 Additional information

Precautions

• When the transmitter is not to be used for a long

period of time, disconnect the AC power
adaptor from the AC outlet holding the plug. Do
not pull on the cord.

• Do not leave the wireless stereo headphone

system in a location subject to direct sunlight,
heat or moisture.

Notes on headphones
Preventing hearing damage

Avoid using headphones at high volume. Hearing
experts advise against continuous, loud and
extended play. If you experience a ringing in your
ears, reduce the volume or discontinue use.

Caring for others

Keep the volume at a moderate level. This will
allow you to hear outside sounds and to be
considerate to the people around you.

If you have any questions or problems concerning
the system that are not covered in this manual,
please consult the nearest Sony dealer.

Be sure to bring the headphones and the
transmitter to the Sony dealer when requiring
repair work.

Disposing of the headphones

Be sure to remove the built-in rechargeable
batteries from the headphones before you
dispose of the headphones.
First remove the left headphone’s ear pad.
You will see six screws. Remove the six screws
and open the housing.

English

Note

This device complies with RSS-210 of Industry
Canada. Operation is subject to the following two
conditions: (1) this device may not cause
interference, and (2) this device must accept any
interference, including interference that may cause
undesired operation of the device.

TUNING
control

VOL control

N

 Getting started

Unpacking

Check that you have the following items:

• The headphones
• The transmitter
• AC power adaptor
• Unimatch plug adaptor (stereo mini jack 

t

stereo phone plug)

• Connecting cord (phono plugs 

y

 stereo mini

plug), 1 m

Approx. charging
hours

1

24**

Approx. using time*

MDR-
RF945RK

50 minutes

20 hours

MDR-
RF915RK

55 minutes

23 hours

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