Sony XDR-S40DBP, Service Manual

Page: 11 / 28

XDR-S40DBP
11
L-ch
R-ch
L-ch
R-ch
L-ch
R-ch
4. FM RECEPTION CHECK
Procedure:
1. Input the following signal from signal generator to FM antenna
input.
Output frequency: 87.5 MHz
Deviation: 75 kHz/M+S 27 %
Modulation: 1 kHz
Output level: 80 dBuV/m
2. L and R channels are outputted from the signal generator.
3. AC adaptor is inserted in DC jack (J201).
4. Press the [
?/1
] button to turn the power on.
5. Checks that there is no “ ” mark in the upper right of the
liquid crystal display.
6. Press the [DAB/FM] button, change to FM function.
7. Press the [
v
] or [
V
] buttons, change to the frequency of “87.5
MHz”.
8. [– VOL +] jog is turned to center, headphone is inserted in
headphone jack (J202) and it checks that the sound is outputted
from headphone.
It checks that there is no defect. Monaural, reception cannot be
carried out and sensitivity is weak, etc.
9. [– VOL +] jog is turned in the counterclockwise direction to a
minimum. The sound from a headphone becomes small suit-
ably, and it checks that there is no defective sound quality.
(Sound is not outputted at the time of a minimum)
10. [– VOL +] jog is turned in the clockwise direction to a maxi-
mum. The sound from a headphone becomes large suitably,
and it checks that there is no defective sound quality.
11. Headphone is pull out from the unit. It checks that the unit is
struck 3 times lightly and the sound from a speaker does not
have interruption and defective sound quality.
12. [– VOL +] jog is turned in the counterclockwise direction to a
minimum. The sound from a speaker becomes small suitably,
and it checks that there is no defective sound quality.
(Sound is not outputted at the time of a minimum)
13. [– VOL +] jog is turned in the clockwise direction to a maxi-
mum. The sound from a speaker becomes large suitably, and it
checks that there is no defective sound quality.
14. The audio connecting cord from an oscilloscope is inserted in
the headphone jack (J202).
15. The stereo waveforms are checked with an oscilloscope.
Example:
16. R channel is outputted from the signal generator, and R-chan-
nel waveform is checked with an oscilloscope.
Example:
17. L channel is outputted from the signal generator, and L-chan-
nel waveform is checked with an oscilloscope.
Example:
18. The audio connecting cord from an oscilloscope is pull out the
headphone jack (J202).
19. Press the [
?/1
] button to turn the power off.
20. Pull out the AC adaptor.