Panel Facilities - Pioneer SX-680 Service Manual

2. FRONT PANEL FACILITIES
POWER METERS
These meters allow you to read out the rated power leve!
when speakers with a nominal impedance of 8 ohms are
connected to the receiver's speaker terminals.
NOTE:
These values are related to the impedance of the
speakers and they vary according to the frequency.
In order to find out the exact output level, connect an
8-ohm dummy load instead of the speakers.
POWER SWITCH
Depress this button (in the ON position) to supply power
to the receiver. There will be a short delay when it is set
to ON, because the muting circuit has been actuated to
suppress the unpleasant noise that is sometimes generated
when the power is switched on and off.
PHONES JACK
Plug the headphones into this jack when you want to
listen through your stereo headphones.
Release both SPEAKERS buttons if you want to listen to
the sound through your headphones only (This means
that both buttons will be released).
SPEAKERS SWITCHES
Depress the button corresponding to the speakers con-
nected to the SPEAKERS terminals (A or B) on the rear
panel. You can depress both of these buttons to listen to
sound from two pairs of speaker systems at the same time.
BASS AND TREBLE CONTROLS
Use these controls to adjust the bass and the treble. If you
tun the BASS control to the right from its center posi-
tion, you will be able to emphasize the sound in the
low-frequency range. Conversely, turning this control left
from the center position will attenuate the sound.
You can use the TREBLE control to adjust the sound in
the high-frequency range.
TAPE MONITOR INDICATOR
With either of the TAPE MONITOR switches set to ON,
the TAPE MONITOR indicator lights up. This lamp
indicates the receiver is monitoring or playing back the
tape on the tape deck connected to the TAPE jacks.
SOURCE INDICATOR
With either of the TAPE MONITOR switches set to OFF,
the SOURCE indicator lights up. This lamp indicates the
receiver is playing the program source; AM broadcast,
FM broadcast, record on the turntable, or another com-
ponent connected to the AUX jacks.
sass TREALE
mone « a
e
OFS PISS
oN
cp
©
nae haan nar naan
This switch is a combination of the FM muting switch and
the mode select switch. When the button is left unde-
pressed (ON position) the reproduction is in STEREO
mode, while the FM muting function acts to suppress
unpleasant interstation noise while tuning between FM
stations when listening to FM broadcasting. When the
button is depressed (OFF position), however, reproduc-
tion is in MONO mode, while the FM muting function
does not act, thus enabling suitable reception of weak
radio stations when tuning in to the FM broadcasting
station.
NOTE:
Recording stereophonically with the mode select switch
(MODE/FM MUTE) in the MONO position may cause
deterioration in channel separation.
MODE EM MUTE
eREO CN
MODE/FM MUTING SWITCH —
—DIAL POINTER
FUNCTION
ane
MONO ah cere (
a
wy
ae
sen
oN rors OO 4 OC
A
This pointer indicates the broadcasting stations.
STEREO INDICATOR
This indicator lights up when the receiver is tuned in to
receive a stereo broadcast.
AM/FM TUNING METER
When tuning in to FM stations, position the meter pointer
in the center of FM area for optimum reception. In the
case of AM stations, tune for maximum meter deflection
toward the right of the scale.
voupime
TaPe MONITOR toes
Max
G) PIONEER srenco secewer sx-680
FUNCTION SWITCH
Use this switch to select the program source. For a second
after the switch is selected, no sound will be heard. This is
due to the operation of the muting circuit, which mute
the unpleasant switching noise generated when the FUNC-
TION switch is selected.
AM: When listening to AM broadcasting.
FM: When listening to FM broadcasting.
The STEREO indicator lights up when the
receiver is tuned in to an FM stereo broadcast.
PHONO: When playing a record on the turntable con-
nected to the PHONO jacks.
When listening to an audio component con-
nected to the AUX jacks.
TUNING KNOB
Use this to tune in to broadcasting stations.
Select the station and tune for optimum reception by
observing the dial scale and the AM/FM tuning meter.
VOLUME CONTROL
Use this control to adjust the output level to the speakers
and headphones. Turn it clockwise to increase the output
level. No sound will be heard if you set it to MIN.
LOUDNESS SWITCH
Depress this button (ON position) when listening at a low
volume. The frequency response of the human ear varies
according to the listening volume, and setting this switch
to the ON position compensates for hearing response by
emphasizing the bass and treble.
BALANCE CONTROL
Use this control to balance the volume of the left and
right channels. First, however, set the mode select switch
(MODE/FM MUTE) to MONO. If the sound appears to be
louder on the right, it means that the volume of the right
channel is higher. Turn the BALANCE control to the
left and adjust. Conversely, if the sound appears to be
touder on the left, it means that the volume of the left
channel is higher. Therefore, turn the BALANCE control
to the right and adjust. After adjusting, return the mode
select switch (MODE/FM MUTE) to STEREO.
TAPE MONITOR SWITCHES (1, 2)
Depress the switch 1 with a tape deck which is connected
to the TAPE 1 jacks (REC and PLAY) when you want to
monitor the playback or recording of a tape. The tape
on a deck which is connected to the TAPE 2 jacks (REC
and PLAY) can be similarly monitored by depressing
the switch 2.
NOTE:
Set these switches to the released (OFF) position when
you listening to records or a broadcasting.
°