Technics ST-CH505 Service Manual

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7
ST-CH505
ST-CH505
H H 7 . : AM (LW/MW) si Ii : i
@ Schematic Diagram eTuner circuit (parts tist on pages 23~27) ee AE WW) aloralline ——) + FM atonal ine
25> : AM (LW/MW) OSC signal line ooo : FM OSC signal line
Positive voltage line
AF signal line
1 2 3 4 5 6 7 8 9 10
@\Indicated voltage values are the standard values for the unit measured by the DC electronic circuit tester (high-impedance) with the chassis taken as standard.
Therefore, there may exist some errors in the voltage values, depending on the internal impedance of the DC circuit tester. No mark: FM mode ( ): MW mode ce >: LWmode
EQ tuner circuit
For (£G) area.
For (E,GNJareas.
2SC2787FLITA
racoe”-- SSCErSEKTA
A ee ace yw eoooe eden saws eee ee 4 Z120 FM FRONT END (RALOOI9)
2SK544F-AC 2SC2786EMKTA 0.47yH CF201_ |. 28K238 ch eee ee ERY MFO Me he 28C2620 Soar ae |
a | RF AMP rs 22p FM MIXER eC Of a lf o 43 H 22 FM MIXER x I
--— i 5.6P ) 8 f —I— i
JKION 1 ae : mh z 14 I }
1 FM ANT© >(1) iT OSE L-t-4
(759) ! H ! ry 5 z itr] . | 8 (6) 2 a
= 5 5! SIGN
@— | iwss 8 3 \a 83 8 3 | ae at
For (GN) ie a ee ee I
areas. (5) = |
FM ANT H |
JKIOI 1 1
r—@ { |
1 750 1 | |
| |
| |
t |
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4
28C2996
Qiol BUFFER AMP
2sce7a7LTA ti (tsi YY: LC -- -- - - -- — -- - - - - -
FM IF AMP es
— = Qio2
Pa
Ss
38
2SC2787LTA
AMILW/MW)0SC 38 osT es EME AME,
signal
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f
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feb
oe
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aio2
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25 (ov) 2 For (E,GN) 5600P---(E,6N)
AM ANT 5 ow areas. (ov) Q106 ©1391 s200P---(€6)
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bee
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LOOP ANT o =] RIO3 ¢ RI47 RI43
6
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33
----
(EG)
LAI830-H
AF
SIGNAL
470K
2.2K
D { FM/AM IF AMP,DET/AM OSC,MIX/FM MPX (ich) 27v
16V10--- (E,GN) A x 14.7)
3
cis
{iévioo-teo)
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3
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R39
3 = 2.7K
c
od
oy
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QI9I-193 rias{ ik (E,GN)
D 2SC33IIAIRTA 820-~ (EG)
é LW/MW SWITCHING RI48
87
5MH1=——108MHr
470K
RI76 A
390
7
ar
Oz
S
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1K---(E,
GN)
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:
STEREO
€140
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RECEIVED SIGNAL: OV
3.9K-y(E,GN) ; cNIOl
=
Rug
vie
oT
7 8.2K-~ (EG) +8(2)
@103, 104 ne is ee Da a C4
zecdreatsr™ Tre
FM/AM(LW/MW) aa B (J ST EYE To BI coNNECTICN
LOOP FILTER | —} 15} va (2) CIRCUITICNIOS)
Y aw c Ly sen) | (Pace 11)
et b, 8 C1) GND
a 14.7
F 1c102 Bug Bus Bug x3 cise We
Lc7218
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Seats
PLL FREQUENCY me a* a? marests Pot
NTHESIZER (sj 00
(uw) SYNTH ae, Si
> aon
| ae Len out 10 connectia,
(3) ce (HICIRCUITICNIO2))
[eS ecnour | (Paee 1)
O)
F H
S22KHr=1611K
Hz
:

Technics ST-CH505 Specifications

General

Brand	Technics
Model	ST-CH505
Category	Tuner
Language	English