Block Diagram - Pioneer SX-6 Service Manual

@) PRESET-VOLUME SWITCH
This is depressed when the volume level is to be set to
the preset level (the PRESET STEP indicator lights).
When presetting the volume level, depress the MEMORY/
STOP switch with the volume level still indicated on the
display, and then depress the PRESET-VOLUME switch.
@) STATION CALL SWITCHES
These are pressed to call out preset broadcasting stations
and to preset the station.
To call out a station, first set the desired frequency band
using the FM or AM switches and then press the desired
switch.
@) INPUT INDICATORS
These light when the INPUT (PHONO or AUX/VIDEO)
switch is pressed.
@) AUTO/MANUAL SELECTOR
This is used to select the reception mode.
AUTO (released position): Auto tuning is selected in
accordance with the position selected by the STATION
SCAN/STATION SEARCH selector on the right.
MANUAL (depressed position): For manual tuning
Depress the TUNING switch and tune in the station.
manually. Each time the TUNING switch is depressed,
the frequency changes in 100kHz steps during FM
reception and in 9kHz or 10kHz steps during AM
reception in accordance with the position of the AM
CHANNEL STEP switch. When the TUNING switch is
kept depressed, the frequency is continuously scanned.
Tuning stops when the upper or lower limit of the
frequency band is reached.
STATION SCAN/STATION SEARCH
SELECTOR
This is used to select the auto tuning mode when the
AUTO/MANUAL selector switch on the left is at AUTO.
STATION SCAN: When the TUNING switch is depressed,
the broadcasting stations start to be scanned and this
procedure stops once a station has been picked up.
The program of that station is heard for about 5
seconds. The tuning operation then resumes and sound
is heard in the same way. Each of the stations is thus
picked up in turn.
When the MEMORY/STOP switch is depressed once
you hear the sound of the desired program, the tuning
Operation stops and the unit is set to the reception
mode.
STATION SEARCH: When the TUNING switch is de-
pressed, the broadcasting stations start to be scanned,
but this operation stops once a station has been picked
up and the unit is set to the reception mode. Depress
the TUNING switch if the station picked up is not the
one desired. The tuning operation now starts over
again.
@ TAPE MONITOR INDICATOR
This lights when the TAPE (1 or 2/ADPT) switches are de-
pressed.
MEMORY/STOP SWITCH
This switch is used to preset the broadcasting stations into
the STATION CALL switches or to preset the desired
volume level into the PRESET-VOLUME switch.
This switch is also used to stop the tuning operation
during the STATION SEARCH or STATION SCAN
functions.
@) TAPE SWITCHES
1: Depress this switch to monitor the recording or
playback of a tape on the tape deck connected
to the TAPE 1 jacks (REC and PLAY).
2/ADPT: This is depressed when using a tape deck or
adaptor unit connected to the rear panel TAPE
2/ADAPTOR jacks.
NOTE:
Depress switch 1 and release switch 2/ADPT when dubbing a
tape in the deck connected to the TAPE 7 jacks onto a tape in
the deck connected to the TAPE 2/ADAPTOR jacks.
62 MONO MUTE OFF SWITCH
The sound is heard in mono when this switch is set to the
depressed position. Normally, the switch is kept at the
released position. During FM or AM reception, the noise is
reduced and reception is made clear. When the station is
distant and its signals are weak, depress the switch and
tune in the station manually.
63 SUBSONIC SWITCH
The subsonic filter with the 15Hz cut-off frequency is
actuated when this switch is depressed. This filter serves
to attenuate the frequencies lower than 15Hz with a
6dB/oct. slope and, therefore, it can be used to suppress
the ultra-low-range noise which is generated by record
warp and other factors. This noise cannot actually be
heard by the ear but it can cause cross modulation distor-
tion and even speaker damage. Use this switch when
required during record play.
@4 LOUDNESS SWITCH
When listening to a performance with the VOLUME level
is low, depress this switch and the bass and treble will be
accentuated.
When the volume is low, the human ear finds it harder to
hear the bass and treble than when the volume is high.
The LOUDNESS switch is thus designed to compensate
for this deficiency.
3. BLOCK DIAGRAM
FM TUNER
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2 12 43
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1 IN OUT 6
{PA3001-A)
21IN LOUT4
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R OUT
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3
(HAIIS6W-P)
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ROUT 5
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CIRCUIT 4 3 1FM 7
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EQUALIZER AMP
35.6 dB( AT tkHz)
(NJM4558DXC)
| TAPE 1 ADAPTOR !
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FUNCTION ee
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(PA4008) REC PLAY OUT/ IN/
TORCH REC PLAY
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TARE ADAPTOR /TAPE 2
—+35V(+BS)
+ 42.5V(+B1)
+28V(+B2)
+418.6 Vi +B3)
VOLUME
& MU
(PASO04)
+ BALANCE
TING
+12.2V(+B6)
+ 4.9V (+ B7)
+4.9V (+88)
OVERLOAD
DETECTOR
TONE CONTROL
SPEAKERS ~——~B