Sony TMRRF-830-R Service manual

TMR-RF830R

SERVICE MANUAL

REVISED

Ver 1.2 1999. 09

TMR-RF830R is the component model block one in MDR-RF830RK.

COMPONENT MODEL NAME FOR MDR-RF830RK

Wireless Stereo Headphones MDR-RF830 Transmitter TMR-RF830R

SPECIFICATIONS

AEP Model

UK Model

General

Carrier frequency

Channel Ch1, Ch2 Modulation FM stereo Frequency response

Transmitter

Power source DC 9 V: supplied AC power adaptor Audio input phono jacks/stereo mini jack Dimensions Approx. 120 mm dia × 290 mm

Mass Approx. 155 g (5.5 oz.)

Design and specifications are subject to change without notice.

863.32 – 863.67 MHz

20 – 20,000 Hz

(43/4 × 111/2 in.)(w/h)

MICROFILM

TRANSMITTER

SECTION 1

)

DISASSEMBLY

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

1-1. TX BOARD, VCO BLOCK

Cabinet (Upper

Vco block

Remove

solder

Remove solder

TX board

Remove solder

TX shield plate

— 2 —



Screws +P2 × 10

Cabinet (Lower)

SECTION 2

ELECTRICAL ADJUSTMENTS

TMR-RF830R

Note :

1. The transmitter section adjustments should be completed before performing the headphones section adjustment.

2. On adjusting the transmitter section, use the headphones as a jig.

Transmitter TMR-RF830R

Headphones MDR-RF830

Setting :

AF signal generator

set

TMR-RF830R

L-CH (J403)

Telescopic antenna

Frequency counter

8 cm

Headphones

set

TMR-RF830R

1. Set the noise filter SW to OFF.

2. Set the channel to CH2.

3. Input a signal of 1 kHz 316 mVrms to the L-CH (J403).

4. Measure the pin 1 voltage of the TX board IC403 using an digital voltmeter (AC range) and make sure the value is 220 to 250 mVrms. If the measured value is other than the specified value, adjust to 235mVrms by turning the RV401 on the TX board.

Connection points and Adjustment Location :

TX board (See page 4)

Sub-Carrier Frequency/Level Check and Adjustment

1. Set the noise filter SW to OFF.

2. Set the channel to CH2.

3. Input a signal of 1 kHz 316 mVrms to only the L-CH (J403).

4. Connect a frequency counter and an oscilloscope between the pin 2 of RV402 and GND.

5. Set the TX board L-CH (J403) input to OFF (not doing so will cause modulation in the sub-carrier, preventing correct measurement)

6. Check to make sure the frequency counter reading is 49 to 51kHz. If the measured value is other than the specified v alue, adjust the frequency to 50 kHz by turning the R V405 on the TX board. In addition, check to make sure the oscilloscope waveform is as follows :

[TX BOARD] (Component side)Sub-Carrier (L-R) Modulation Check and Adjustment

Oscilloscope

-2

-1

J403

(L-CH)

J402

(R-CH)

Frequency counter

Sub-Carrier Frequency Adjustment

S401 Noise Filter ON/OFF Switch

MDR-RF830

Battery terminal (DC 3V)

Send Frequency Check and Adjustment

1. Set the noise filter SW to OFF.

2. Input a signal of 1 kHz 40 mVrms to only the L-CH (J403).

3. Connect a telescopic antenna to the frequency counter input and extend the antenna to a length of approximately 8 cm.

4. Place TX board close to the frequency counter, then measure the frequencies of CH1 and CH2 and make sure the values are as follows:

CH1 : 863.27 to 863.37 MHz

CH2 : 863.62 to 863.72 MHz When the frequency is not satisfied the specified value, first set the channel switch (S402) to “2” and adjust CH2 frequency with L412, next set it to “1” and adjust CH1 frequency with L413. When completed with adjustment, recheck the frequecies of CH1 and CH2.

Main-Carrier (L+R) Modulation Check and Adjustment

1. Set the noise filter SW to off.

2. Set the channel to CH2.

3. Input a signal of 1 kHz 316 Vrms to the L-ch (J403) and the RCH.(J402)

4. Measure the pin 2 voltage of the TX board RV 404 using a digital voltmeter (AC range) and make sure the value is 75 to 95 mVrms. If the measured value is other than the specified value, adjust to 85mVrms by turning the RV 404 on the TX board.

80 – 100mVp-p

7. When the waveform P-P level is not satisf ied the specified value, adjust to 90mVp-p with RV402.

(Perform the check and adjustment within one minute since the transmitter A UTO OFF function will be acti vated approximately one minute after setting the transmitter L-ch input to OFF. If the A UT O OFF function activ ates, set the L-ch input to ON, set TX board to AUTO ON, set the L-ch input again to OFF, then make the check adjustment.)

Connection points and Adjustment Location :

TX board (See page 4)

Digital voltmeter

(AC range)

Main-Carrier (L+R) Modulation Adjustment

RV401 : Sub-Carrier (L– R) Modulation Adjustment

RV405 : Sub-Carrier Frequency Adjustment

CHANNEL

-1 -2

RV402

Sub-Carrier Level Adjustment

L413 (CH1)

L412 (CH2)

RV404 : Main-Carrier (L+R)

Modulation Adjustment

Sub-Carrier (L-R) Modulation Adjustmen

Digital voltmeter

(AC range)

Send Frequency Adjustment

Connection points and Adjustment Location :

TX board (See page 4)

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