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
3
2
Vco block
7
Remove
solder
8
Remove solder
9
TX board
7
Remove solder
6
TX shield plate
5
TX shield plate
1
— 2 —
4
Screws +P2 × 10
Cabinet (Lower)
SECTION 2
t
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
45
13
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
-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)
— 3 — — 4 —
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