Onkyo TX-2500 Service Manual page 7

TX-4500 BLOCK DIAGRAM
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af 19KHz
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ADJUST (3) STEREO
Rii4
RELAY
SCHMITT QO
TRIGGER
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X105a119 0120
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T CUIT
ZERO CROSS GATE CIR
DETECTOR
131
C ) TUNING | SENSOR AMP
KNOB 0126
S.METER
AM ANT ©
To SELECTOR
SS SENSOR SW
<>
oe $801
a SELECTOR ,
/ /
/ /
PHONO 1 / j TAPE
| MONITOR MODE — VOLUME LOW HIGH PRE AMP BALANCE
$802~S804 $807 R356 FILTER FILTER a3 R382
PRE MAIN
EQUALIZER TONE AMP
AMP Q351.0352 / | p \ CO) nbtosoe Or" O—--—© L-ourT
PHONO 2 Q301~ Q303 0353
PROTECTOR
CIRCUIT
THERMO
AMP
Q504
RIAA
LOUDNESS BASS TREBLE
$808 R39 R372
fig—6