DOWNLOAD Sony SLV-L56AR / SLV-L76HFAR / SLV-L86HFAR Service Manual ↓ Size: 18.24 MB | Pages: 79 in PDF or view online for FREE

Model
SLV-L56AR SLV-L76HFAR SLV-L86HFAR
Pages
79
Size
18.24 MB
Type
PDF
Document
Service Manual
Brand
Device
VCR
File
slv-l56ar-slv-l76hfar-slv-l86hfar.pdf
Date

Sony SLV-L56AR / SLV-L76HFAR / SLV-L86HFAR Service Manual ▷ View online

7-3
2-4.
AUDIO  SYSTEM  ADJUSTMENTS
• Adjust both Lch and Rch.
[Connection]
Fig. 7-2-4.
2-4-1.
Hi-Fi Audio System Adjustment
(SLV-L76HF/L86HF)
• Set switches and knobs to the following positions to make ad-
justment unless otherwise specified.
INPUT SELECT switch ................... LINE
AUDIO MONITOR ......................... STEREO
[Adjustment Sequence]
1. AF Switching Position Adjustment
2. Frequency Responce Check
3. Overall Level Characteristic and Distortion Factor
Check
4. Overall S/N Check
1.
AF Switching Position Adjustment (MA-323 Board)
Purpose:
Adjust the interval between A CH and B CH of tape playback
output.  Improve the interchangeability with other tapes and sets.
When it is out of order, noisy sound is increased and big noise is
heard.
Mode
PB
Signal
Alignment tape SP mode color
bar
Measurement point
CH1: Pin 2 of  CN501
CH2: Pin 1 of CN341
Measuring Instrument
Oscilloscope
Specified Value
Fig. 7-2-5
Adjusting Method:
1) Connect MA-323 board JS140 to the GND for about 1 secont
to activate the RF switching position adjustment mode.
2) Press the record button to activate the AF switching position
adjustment mode.
3) Check appear “A H” on FL display.
4) Using the channels + and – buttons, minimize a chipped por-
tion.  At this time, confirm that a noisy sound is not heard.
5) Press the pause button.
Fig. 7-2-5.
2.
Frequency Responce Check
Purpose:
Confirm that the frequency characteristic is within the specifica-
tion.
Mode
REC and PB (SP, LP mode)
Signal
400 Hz, –7.5 dBs
20 Hz, –7.5 dBs
20 kHz, –7.5 dBs
Measurement point
Audio output terminal
Measurement equipment
Audio level meter
Specified value
0 ± 2 dB
NOTE: 
Tape path adjustment must have been completed.
Confirmation Method:
1) Supply a signal of 400 Hz, –7.5 dBs to both L and R channels
of Audio Line Input.
2) Connect the audio level meter to the Audio Line Output.
3) Adjust the attenuator so that the audio level meter will indi-
cate –7.5 dBs.
4) Make recording.
5) Set an audio line input signal to 20 Hz and make recording.
6) Set an audio line input signal to 20 kHz and make recording.
7) Playback a recorded portion, and measure output levels at 400
Hz and 20 Hz and 20 kHz.
8) Confirm that the 20 Hz and 20 kHz playback output level within
a range of the 400 Hz playback output level 0 ± 2 dB.
Audio
generator
Attenuator
600 
47 k
VCR
Audiolevel meter or
distortion meter
AUDIO LINE OUT
AUDIO LINE IN
   Feed signal both 
   channelssimultaneously.
CH2
CH1
RF SWP
OK
NG
7-4
3. Overall Level Characteristic and Distortion Factor
Check
Purpose:
Check the record level, play level, and distortion factor against
the reference input.
Mode
REC and PB (SP mode)
Signal
400 Hz, –7.5 dBs
Measurement point
Audio output terminal
Measurement equipment
Audio level meter and distortion
factor meter
Specified value
Playback level: –7.5 ± 2 dBs
Distortion factor: 1% or less
Confirmation Method:
1) Supply an audio signal of 400 Hz, –7.5 dBs simultaneously to
both L and R channels of Audio Line Input.
2) Make recording
3) Play back a recorded portion.
4) Confirm that a playback level is –7.5 ±2 dBs.
5) Confirm that a distortion factor is within 1%.
4. Overall S/N Check
Purpose:
Confirm that the S/N is within the specification.
Mode
REC and PB (SP mode)
Signal
Short
Measurement point
Audio output terminal
Measurement equipment
Audio noise meter
Specified value
–67.5 dBs or less
Confirmation Method:
1) Connect both L and R channels of audio line input to the GND.
2) Start recording.
3) Play the recorded part to confirm that the noise is below –67.5
dBs.
2-4-2.
Normal Audio System Adjustment
• Make adjustment in the SP mode, unless otherwise specified.
Use a normal VHS cassette for an adjustment tape.
• Set AUDIO MONITOR  to normal.
[Adjustment Sequence]
1. ACE Head Adjustment
2. E-E Output Level Check
3. Frequency Responce Check
4. Overall Level Characteristic and Distortion Factor
Check
5. Overall S/N Check
1. ACE Head Adjustment
Refer to the service manual of VHS MECHANICAL
ADJUSTMENT 
VI
.
2. E-E Output Level Check
Purpose:
Confirm that the output level against the reference input is within
the specification.
Mode
E-E
Signal
L, R: 400 Hz, –7.5 dBs
Measurement point
Audio output terminal
Measurement equipment
Audio level meter
Specified value
–7.5 ± 2 dBs
Confirmation Method:
1) Simultaneously input a signal of 400 Hz, –7.5 dBs to both L
and R channels of Audio Line Input.
2) Confirm that the audio output level is –7.5 ± 2 dBs.
3. Frequency Responce Check
Purpose:
Confirm that the frequency characteristic is within the specifica-
tion.
Mode
REC and PB (SP mode)
Signal
400 Hz, –30.0 dBs
7 kHz, –30.0 dBs
Measurement point
Audio output terminal
Measurement equipment
Audio level meter
Specified value
1 ± 3 dB
Tape path adjustment must have been completed.
Confirmation Method:
1) Supply a signal of 400 Hz, –30.0 dBs to both L and R channels
of Audio Line Input.
2) Connect the audio level meter to the Audio Line Output.
3) Adjust the attenuator so that the audio level meter will indi-
cate –30.0 dBs.
4) Make recording in the SP mode.
5) Set an audio line input signal to 7 kHz and make recording.
6) Playback a recorded portion, and measure output levels at 400
Hz and 7 kHz.
7) Confirm that the 7 kHz playback output level within a range
of the 400 Hz playback output level 1 ± 3 dB.
7-5
7-6 E
4. Overall Level Characteristic and Distortion Factor
Check
Purpose:
Check the record level, play level, and distortion factor against
the reference input.
Mode
REC and PB (SP mode)
Signal
400 Hz, –7.5 dBs
Measurement point
Audio output terminal
Measurement equipment
Audio level meter and distortion
factor meter
Specified value
Playback level: –7.5 ± 2 dBs
Distortion factor: 4% or less
Confirmation Method:
1) Supply an audio signal of 400 Hz, –7.5 dBs simultaneously to
both L and R channels of Audio Line Input.
2) Make recording
3) Play back a recorded portion.
4) Confirm that a playback level is –7.5 ± 2 dBs.
5) Confirm that a distortion factor is within 4%.
5. Overall S/N Check
Purpose:
Confirm that the S/N is within the specification.
Mode
REC and PB (SP mode)
Signal
Short
Measurement point
Audio output terminal
Measurement equipment
Audio noise meter
Specified value
–46.0 dBs or less
Confirmation Method:
1) Connect both L and R channels of audio line input to the GND.
2) Start recording.
3) Play the recorded part to confirm that the noise is below –46.0
dBs.
2-6.
PARTS  ARRANGEMENT  DIAGRAM  FOR  ADJUSTMENTS
MA-323 BOARD (Side A)
HS-921SF1 BOARD (Side A)
SR-708 BOARD (Side A)
RV201
CN201
6V ADJ
1
9
CN501
CN431
1
4
2
1
JS140
RV750
IC750
13
1
US MPX SEP
2-5.
TUNER  SYSTEM  ADJUSTMENT
[Connection]
Fig. 7-2-6
2-5-1.
Separation Adjustment (SLV-L76HF/L86HF)
Purpose:
Mixed audio signal separate Lch and Rch.
Mode
E-E
Signal
VIDEO:
  color bar
  (87.5% modulation)
AUDIO:
  L
1 kHz 100% modulation
  R no signal
ELECTRIC FIELD:
  60–80 dBs/75 W Tem
Measurement point
Pin !™ of IC750
Measurement equipment
Audio level meter
Adjusting Element
RV750
Specified value
–9.9 ± 0.2 dBm
(700 ± 14 mVp-p)
CN201
6V ADJ
VR201
1
9
47 k
VTR
Audio level
meter
Up channel
convertor
RF IN
8-1
NOTE:
• -XX and -X mean standardized parts, so they may
have some difference from the original one.
• Items marked “*” are not stocked since they are
seldom required for routine service. Some delay
should be anticipated when ordering these items.
• The mechanical parts with no reference number in
the exploded views are not supplied.
• Hardware (# mark) list and accessories and pack-
ing materials are given in the last of the electrical
parts list.
SECTION  8
REPAIR  PARTS  LIST
8-1.
EXPLODED  VIEWS
SLV-L56/L76HF/L86HF
The components identified by mark
! or dotted line with mark ! are criti-
cal for safety.
Replace only with part number speci-
fied.
Ref. No.
Part No.
Description
Remark
Ref. No.
Part No.
Description
Remark
11
1-783-569-11 CABLE, FLAT (FDM-4)
* 12
A-6791-586-A DM-76 BOARD, COMPLETE (L86HF)
* 12
A-6791-588-A DM-76 BOARD, COMPLETE (L56, L76HF)
* 13
A-6791-575-A MF-312 BOARD, COMPLETE (L56, L76HF)
* 13
A-6791-589-A MF-312 BOARD, COMPLETE (L86HF)
14
1-783-568-11 CABLE, FLAT (FMF-23)
15
3-052-716-11 CASE, UPPER
16
3-710-901-61 SCREW, TAPPING
17
1-418-550-11 COMMANDER, STANDARD (RMT-V247E) (L56)
17
1-418-550-21 COMMANDER, STANDARD (RMT-V247F)
(L76HF, L86HF)
18
3-709-133-11 COVER, BATTERY (for RMT-V247E/V247F)
1
X-3949-736-1 PANEL ASSY, FRONT (L86HF)
1
X-3949-737-1 PANEL ASSY, FRONT (L56)
1
X-3949-738-1 PANEL ASSY, FRONT (L76HF)
2
X-3949-102-1 BUTTON ASSY, FUNCTION (L76HF)
3
1-762-844-21 SWITCH, ROTARY
4
3-953-432-01 SPRING (GE), FL
5
3-943-995-31 EMBLEM (NO.5), SONY
* 6
3-977-160-01 INSULATOR
7
3-056-468-11 DOOR (S), CASSETTE
8
3-979-309-61 BUTTON (AV), CENTER (L86HF)
9
3-988-327-21 RING (M), JOG (L86HF)
10
4-921-277-41 SCREW (B2.6X8), TAPPING, BIND
8-1-1. FRONT  PANEL  AND  CABINET  ASSEMBLIES
17
18
16
15
16
14
10
10
12
11
13
not
supplied
not
supplied
5
6
4
10
3
9
8
1
L86HF
L76HF
not
supplied
5
6
4
7
7
7
1
L56
not
supplied
1
5
6
4
2
not
supplied
Page of 79
Display

Click on the first or last page to see other SLV-L56AR / SLV-L76HFAR / SLV-L86HFAR service manuals if exist.