Playback Level Check (Ma-327 Board); Audio System Adjustment; Ace Head Adjustment; E-E Output Level Check - Sony SLV-777HF Service Manual

2-4-4. Recording Chroma Level Check
(MA-327 Board)
Mode Recording (SP)
Signal Color bar
IC201 pin !¢
Measurement point
Measuring instrument Oscilloscope
Specified value A=450 ± 70mVp-p
[Check Method]
1) Confirm the amplitude of recording chroma level becomes the
specified value.
Fig. 6-2-8.

2-4-5. Playback Level Check (MA-327 Board)

Mode Playback
Signal Alignment Alignment tape : SP mode color bar
portion
Measurement point Video LINE OUT terminal
Measuring instrument Oscilloscope
Specified value A=1.0 ± 0.1Vp-p (75Ω terminated)
[Check Method]
1) Check that the playback level satisfies the specified value.
White (100%)
Fig. 6-2-9.
A
A
H
2-5.

AUDIO SYSTEM ADJUSTMENT

• For the adjustment of the audio system, perform in the SP mode
if there is no special notes. Use the alignment tape.
[Connecting Instruments]
Audio line INPUT L/R
Audio
oscillator
Attenuator
• Adjust in the SP mode if there is no special indications.
• Perform the adjustment setting the switch on the following
positions.
• INPUT SELECT switch ............................................. LINE 1
[Adjustment Method]
1. ACE head adjustment.....Refer to the VHS mechanical
adjustment manual
2.

E-E output level check

3.

Overall Output level and distortion factor check

4. Overall noise level check.

2-5-1. ACE Head Adjustment

Refer to the VHS mechanical adjustment manual
MECHANISM)(9-921-647-11).
2-5-2. E-E Output Level Check
Mode
Signal
Measurement point
Measuring instrument
Specified value
[Check Method]
1) Input signal of 400Hz and –7.5dBs to the CJ461 L/R.
2) Check that the audio output level is –7.5 ± 3dBs.
6-5
Audio line OUTPUT L/R
Audio level
47 k Ω
600 Ω
VTR
Fig. 6-2-10.
(S MECHANISM)(9-921-647-11).
E-E
400Hz, –7.5dBs : CJ570
CJ570
Audio level meter
–7.5 ± 2dBs
meter
or
distortion
meter
(S