Technics RS-B205

@ ELECTRICAL PARTS LIST
Notes:
1.
Part
numbers
are
indicated
on
most
mechanical
parts.
Please
use
this
part
number
for
parts
order.
2.
Important
safety
notice:
Components
identified
by
/\
mark
have
special
charac-
teristics important for safety.
When
replacing
any
of
these
components,
use
only
manufac-
turer’s specified parts.
3.
Bracketed
indications
in
Ref.
No.
columns
specify
the
area.
Parts
without
these
indications
can
be
used
for
all
areas.
Area
* [EK] United Kingdom.
* [EGA] F.R. Germany.
Prat [ ano [pene ncn
INTEGRATED CIRCUITS
Ic 1 AN7014K Integrated Circuit
IC 4 M5218L Integrated Circuit
IC 401, 402
TEA0665 Integrated Circuit
IC 700 AN6888
TRANSISTORS
Q1,2 2SA1309AQS __ Transistor
Q3,4 2SJ103Y FET
Q 13, 14, 15, 16, 17, 18
28C3311AQS Transistor
Integrated Circuit
Q 21,22 28J103Y FET
[EGA] only
Q 23,24 2SD1330R Transistor
Q 300, 301
2SC3311AQS Transistor
Q 600 2SD592ARS Transistor
Q 601 2SB621ARS Transistor
Q 800 2SA1309AQS ___ Transistor
Q 2SD592ARS Transistor
900
DIODES & RECTIFIERS
D1,2 MA165 Diode
D5,6 MA165 Diode
[EGA] only
D 600, 601, 602, 603
1SR35200 Diode
D 604 MA4120-M Diode
D 701, 702
SLR56YC LED
D 703, 704, 705, 706, 707, 708
SLRS6URC LED
D 709, 710, 711, 712
SLRS56YC LED
D713 LN846RP LED
D 800, 801, 803, 807
MA165 Diode
VARIABLE RESISTORS
VR1,2 EVND4AA00B24 P.B. Gain Adj. VR
VR 3,4 EVND4AA00B54 Overall Gain Adj. VR
VR 200 EWCS5SA000A54 Input Level Control
VR 201 EWHFDAF15G15 Balance Control
TRANSFORMERS
T 300 SLO9C19-K Bias Oscillation Coil
T 600
[EK] A SLT5K236SA AC Power Transformer
T 600 [E]
l [EGA]
[EGA] A. SLT5K235SA AC Power Transformer
*
[E]
All
European
areas
except
United
Kingdom.
Paavo [verve
SWITCHES
VR 301, 302 S$ 1, 800, 801
EVND4AA00B15 Bias Current Adj. VR SSH3087
S 200, 201
SSH3700
L1,2 QLQX0343KWA Bias Trap Coil
L 401, 402 $600 A SSH1069
QLM9Z10K MPX Coil
L 403, 404 $s 900 SSP83
ELM7Q306A Skewing Network Coil
S$ 901 SSP83
S$ 902 SSP83
only QJS2003H
QJA0454Z2C
QJA04552C,
Push Switch
(Line/Mic Selector/
Dolby NR IN/OUT Selector/
Dolby B/C NR Selector)
Push Switch
(Metal/CrO, Tape Selector) SPECIFICATIONS _ * Input level control ...MAX
Push Switch
(Power ON/OFF Selector) Playback S/N ratio
Leaf Switch
(Motor Switch)
Leaf Switch (Play Switch)
Leaf Switch (Mute Switch)
Part Name & Description
Mic Jack
Headphones Jack
DIN Jack
m@ SCHEMATIC DIAGRAM
Notes:
(This schematic diagram may be modified at any time with the develop--
ment of new technolgy.)
% This is the basic circuit diagram of this unit.
Note that part of the circuit is subject to change depending on the
areas.
¢ $1-1~S1-4 : Line/mic select switch in “line” position.
e $200, S201 : Tape select switch in “Normal” position.
(S200 =: Metal, $201 =: CrO2, $200, $201 : Normal)
e $600 : Power switch in “on” position.
e¢ $800 : Dolby NR in/out select switch in ‘‘out” position.
e $801 : Dolby B/C NR select switch in “B” position.
¢ $900 : Motor switch in “off” position.
¢ $901 : Play switch in ‘off’ position.
e $902 : Mute switch in “off” position.
¢ Resistance are in ohms (Q), 1/4 watt unless specified otherwise.
1K=1,000(Q), 1M=1,000k(Q)
© Capacity are in micro-farads (uF) unless specified otherwise.
e All voltage values shown in circuitry are under no signal condition and
playback mode with volume control at minimum position otherwise
specified.
Voltage values at record mode.
.Voltage values at CrO2 tape mode.
.Voltage values at Metal tape mode.
B.... .Voltage values at Dolby B NR mode.
c ....Voltage values at Dolby C NR mode.
For measurement use EVM.
e (————_) indicates B (bias).
E ) indicates the flow of the playback signal.
* (<>) indicates the flow of the record signal.
¢ Important safety notice A
The shaded area on this schematic diagram incorporates special features important
for protection from fire and electrical shock hazards.
When servicing it is essential that only manufacturer's specified parts be used for
the circuit components in the shaded areas of the schematic.
* Caution |!
IC and LSI are sensitive to static electricity.
Secondary trouble can be prevented by taking care during
repair.
* Cover the parts boxes made of plastics with aluminum foil.
%* Ground the soldering iron.
%* Put a conductive mat on the work table.
* Do not touch the legs of IC or LSI with the fingers directly.
@ EQUIVALENT CIRCUIT
1C700: AN6888
* Test tape...QZZCFM
Overall distortion
* Test tape
...QZZCRA for Normal
...QZZCRX for CrO,
...QZZCRZ for Metal
Overall S/N ratio
* Test tape...QZZCRA
Less than 3.5%
CrO2, Metal
Less than 4%
Greater than 43dB
(without NAB filter)
1 2 3 4 5
Ei MAIN CIRCUIT SECTION
AW
‘O—Y
Rt
22K
$1-2
$1-4
S1-1
$1-3
LINE
IN
(
)
line
<>
mic
line
«>
mic
line
<>
mic
line
<>
mic
OX
1
559
5So
|
9So
SS¢
|| am
a) Ez
MIC
ob
|
.
%
peee
ger
See
4
SS
=
C10 = R24
1200P 100
Q3, 4
28J103Y
HEAD SELECT
Bias Current Adj.
a Play SW
Mute SON with"
c40
0.0012
L2 R70
30mH 10K
ui R69
30mH 10K
7 C39
330P 0.0012
ae
Bias
Current Adj.
5. R49
0.0082 27K 2.7K
C31
0.0033
VR301
100K(B)
VR302 =
100K(B)
R50
2.7K
Q15--18
2SC3311A
TAPE SELECTOR
t=) 0
ie Metal:0.7
0
Metal:0.7
(Ds
Metal:0.7
R815 10K R816 10K
Q300,
301
Gy
TAPE
SELECTOR
CIRCUIT
SECTION
2SC3311A
BIAS
OSC
$201-1
$200-1
$200-2
$201-
2
Normal++Cr02
Normal<>Metal
Normal<>Metal
Normal<»Cr02
YVO®Q OO®@ Y © @ YO © @
7300
R200 220
R201
BS R202
10
C303 0.0033
Ly
EHEAD >< ) toy @