Pioneer SX-1250 Service Manual page 7

S P E A K E R B U T T O N S
Three sets of speaker terminals, A, B, and C, are provided
on the rear panel, and the required speaker systems can be
selected by depressing the SPEAKERS buttons as follows:
A . . . . . . . . . . .
S p e a k e r s y s t e m s A o p e r a t e
B . . . . . . . . . . . S p e a k e r s y s t e m s
B o p e r a t e
C , . . . . . . . . . .
S p e a k e r s y s t e m s C o p e r a t e
NO?ESr
1. Whetr any two buttons (A+8, B+C, C+A) ore de'
preaeed simultaneously, the eorresponding pairs of
speaker systems will come into operation. Howeuer, it
is not possible to operote all three speaher systems ot
the same time, euen though all the buttons ore
depressed.
2. For priuote listening through heodphones, return all
the SPEAKERS buttons to the OFF (undepressed)
Dosition.
PHONES 'ACK
Accepts stereo headphones.
W A R N I N G :
Do not plug a microphone into the PHONES jach os may
domage the microphone.
POWER SWITCH
After turning this switch ON there is a delay of some 6 to
8 seconds, during which time the protection circuit
operates to eliminate unpleasant norse.
TWIN BASS CONTROLS
Adiust low frequency tone.
100H2:
Adiusts frequency band below 400H2. Control
effectiveness at 100H2 is r10dB.
50Hz:
Provides additional control for the frequency
band below 200H2. Control effectiveness at
5 0 H z i s r 5 d B .
TONE SWITCH
I n t h e O F F ( u p ) p o s i t i o n , t h i s s w i t c h c a u s e s t h e a m p l i f i e r
section to operate with a flat frequency response regard'
less of the tone control setting.
F M T U N I N G M E T E R
With the SIGNAL meter needle deflected to
make fine adiustment by centering the FM
m e t e r n e e d l e ( i n d i c a t i n g o p t i m u m r e c e p t i o n ) .
S I G N A L M E T E R
the right,
T U N I N G
TUN
Sele
obs
stG
Ft\4|
Lea
For AN4 and
Al\4 tuning:
F M t u n i n g :
Flvl station tunings.
Tune for maximum deflection of the
SIGNAL meter needle to the right.
Both the SIGNAL and FM TUN ING meters
work together. The optimum point of the
S I G N A L m e t e r n e e d l e i s t h e s a m e a s i n A M
tuning. Then use the Fl\4 TUNING rn€ters.
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S P E A K E R S Y S T E M I N D I C A T O R
F M S T E R E O I N D I C A T O R
LOW CUT (30H2) FILTER BUTTON
when low-oitched rumble {from turntable motor or other
source) is obstrusive depress this button to provide
l2dBloctave, attenuation at frequencies below 30H2. lf
no interference is experienced, release this button.
H I G H C U T ( 8 k H z ) F I L T E R B U T T O N
When high frequency scratch noise (from worn records or
other source) is unpleasant, depress this button to provide
12dB/octave attenuation at frequencies above 8kHz. lf
there is no interference, release this button.
FM
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