Sanyo VHR-757G Service Manual page 12

2-3. MTS DECODER CIRCUIT ADJUSTMENT for VHR-757G, VHR-757NL and VHR-777EV &
¢ — |f adjusting the MTS Decoder circuit, special equipment ¢ Before making these adjustments, be sure to make the
shown in section 2-4-1. is necessary. adjustments described in section 2-1. " Servo Circuit.",
¢ Improper adjustment will cause loss of performance of section 2-2. "Video Circuit Relay Jig."
stereo sound and bilingual sound detection.
2-3-1. TEST EQUIPMENT AND STANDARDS REQUIRED
Audio Multiplex TV signal Generator
Oscilloscope
AC Voltmeter
Low Path Filter 15 kHz (48dB/oct)
2-3-2. LOCATION OF ADJUSTMENT POINTS Note:
¢ Set the following remote control button to the positions
P36200E indicated below, before making following adjustments.
TAPE SPEED
3in1 Tuner—_
INPUT
2-3-3. SEPARATION ADu.
Measuring Point | Measuring Equipment | Adj. Condition
AUDIO OUTPUT | Audio Multiplex TV E-E mode
fy terminal signal generator
-— VR EURO pin3 (Lch)| Oscilloscope
: \ i RF AGC Low path filter
: : 2X These VRs 15 kHz (48 dB/oct)
. fished with Adj. Location Adj. Value
TN-6 fh}
PWB ih
i 1. Input the output signal of the audio multiplex TV signal
it VR631 : 5 ;
'! [SEPARATION generator into the VCR ANT input terminal.
2. Connect the oscilloscope to the audio output terminal
EURO pin 3 (Lch) of the VCR via the LPF.
3. Set the audio multiplex TV signal generator as follows.
0) Audio signal Rch: 1 KHz 30% modulation
Audio signal Lch: Unmodulation
4. Adjust VR631 (SEPARATION) so that the output of the
audio output terminal (Lch) is brought to its minimum level.
CP-1 PWB (Foil side) Fig. 2-3-1
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