Marantz SD8020 User manual

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MARANTZ
MODEL
SD8000
STEREO
CASSETTE
DECK
INTRODUCTION
This service manual are prepared for use by Authorized
Warranty Station and contains service information for
Marantz Stereo Cassette Deck.
Servicing information and voltage data included in this
manual are intended for use by the knowledgeable and
experienced technician only. All instructions should be
read carefully. No attempt should be made to proceed
without a good undestanding of the operation of the
Cassette Deck.
The parts list furnishes information by which replacement
parts may be ordered from the Marantz Company. A
simple description is included for parts which can be
usually obtained through local suppliers.
.P.W. BOARD
As can be seen from the circuit diagram, the chassis, of the
Mode! SD8000 consists of following units. Each unit
mounted on a printed circuit board is aescribed with in the
square enclosed by bold dotted line on the circuit diagram.
Pre-Amp.......... mounted on P.W. Board PK11
Mic& Line Vol ..... mounted on P.W. Board PK12
Output Vol ........ mounted on P.W. Board PK13
Power Supply ...... mounted on P.W. Board P400
Computer ......... mounted on P.W. Board PK21
Remote Jack ....... mounted on P.W. Board PK26
mounted on P.W. Board PK22
mounted on P.W. Board PK23
Digital & Meter LED ..
Program Selector ....
Progam .......... mounted on P.W. Board PK27
Timer Switch... 2... mounted on P.W. Board PK24
Rec Mute Switch . . mounted on P.W. Board PK25
Relay 2.2 eat es mounted on P.W. Board P800
Photo Cuppler ...... mounted on P.W. Board POO1
Mecha Logic Switch .. mounted on P.W. Board PK31
Sensor Stop Switch . .. mounted on P.W. Board PK32
PK33
FF. Rew Gavernor ... mounted on P.W. Board PMO1
Fuse(PorN)....... mounted on P.W. Board P900
tompudeck SL NIOG
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2. TEST EQUIPMENT REQUIRED FOR SER-
VICING REPLACEMENT
For measuring and checking the Model SD-8000, the fol:
lowing instruments and materials are necessary.
® Audio Oscillator (AF OSC)
@ Attenuator (600 ohm)
e VTVM
® Distortion Meter
@ Oscilloscope
@ Bandpass Filter
@ Wow and Flutter Meter
@ Torque Meter (Cassette T ype)
® Digital Frequency Counter
® Blank Tape (Completely erased with bulk eraer)
bs AC-211 (Normal)
AC-511 (CrO2)
r CS-30 (Fe-Cr)
AC-701 (Metal)
NOTE: If any doubt is noted in a measureé value, use
a new tape.
@ Test Tape (New Tape)
MTT-111 .... Wowand Flutter. Tape Sped.
MTT-212 . Measurement of output lew! and
(MTT-112) Signal to Noise Ratio.
MTT-150 . Adjustment of output levei
MTT-216 . Measurement of Frequency Response
(MTT-116U) (For Normal)
MTT-316 . Measurement of Frequency Response
(MTT-116K) (For CrO2, Fe-Cr)
MTT-121 .... Cross Talk.
MTT-141 .... Channel Separation.
MTT-112B - Playback Signal-to-Noise Rytio.
(W.T.D. only)

TABLE OF CONTENTS
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2.
TEST
EQUIPMENT
REQUIRED
FOR
SERVICING
REPLACEMENT
.........................22...
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SCURCUIT-DESCRIPTION:
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CIRCUIT
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RECORDING
CURRENTSETTING
CIRCUIT
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COMPENSATING
CIRCUIT
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3.5
BIAS
OSCILLATOR
CIRCUIT/ERASE
OSCILLATOR
CIRCUIT
...........
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3.6
CONTROL
CIRCUIT
OPERATION
.........
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DIAGRAM
AND
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LOCATIONS
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8.1.
Pre
Amp.
Assembly
(PK11)
Schematic
Diagram
and
Component
Locations
............
0000
ce ce
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44
8.2
Mic
Line
Volume
Assembly
(PK12)
Schematic
Diagram
and
Component
Locations..............-.c0ccceccee
44
8.3
Output
Volume
Assembly
(PK13)
Schematic
Diagram
and
Component
Locations
.............-..cccceecee
44
8.4
Computer
Assembly
(PK21)
Schematic
Diagram
and
Component
Locations
............0
000 ccc
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47
8.5
Program
Selector
Assembly
(PK23)
Schematic
Diagram
and
Component
Locations..............0cc0ceeeeeee
49
8.6
Power
Supply
and
Bias
OSC
Assembly
(P400)
Schematic
Diagram
and
Component
Locations.................-..
50
8.7
Digital
and
Meter
LED
Assembly
(PK22)
Schematic
Diagram
and
Component
Locations
...............e0ce0ee
50
8.8
Timer
Switch
Assembly
(PK24)
Schematic
Diagram
and
Component
Locations.
.............
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51
8.9
Rec-Mute
Switch
Assembly
(PK25)
Schematic
Diagram
and
Component
Locations.
..............-0cecccccee
51
8.10
Program
Select
Assembly
(PK27)
Schematic
Diagram
and
Component
Locations
.............0.
0c
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52
8.11
Logic
Control
Assembly
(PK31)
Schematic
Diagram
and
Component
Locations...
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8.12
Remote
Jack
Assembly
(PK25)
Schematic
Diagram
and
Component
Locations
............00.
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8.13
Safety
Switch
Assembly
(PK32)
Schematic
Diagram
and
Component
Locations.
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8.14
Safety
Switch
Assembly
(PK33)
Schematic
Diagram
and
Component
Locations...............-00cecceccecae
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8.15
Timer
Relay
Assembly
(P800)
Schematic
Diagram
and
Component
Locations.............00
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8.16
Fuse
Assembly
(P900)
Schematic
Diagram
and
Component
Locations
(N,
TASB
VERSIONS
ONLY)
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Governor
Assembly
(PMO1)
Schematic
Diagram
and
Component
Locations
..............-0.e0ccceeee
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8.18
Photo
Coupler
Assembly
(P001)
Component
Locations...
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CIRCUIT DESCRIPTION
3.1 TAPE SPEED SELECTOR
Tape
speed
is
changed
by
switching
the
motor
speed
to
1,800
rpm
for
1-7/8
ips
(4.75
cm/sec)
or
to
3,600
rpm
for
3-3/4
ips
(9.5
cm/sec).
In
fast-forward
or
rewind
opera-
tion, however, the motor always rotates at 1,800 rpm.
1. R352 is used for precisely adjusting the motor speed
to 3,600 rpm.
2.To precisely adjust the motor speed to 1,800 rpm,
turn the variable resistor built-in the motor.
NOTE:
The
motor
speed
is
known
by
playing
back
the
test
tape
MTT-111
and
measuring
the
reproduced
frequency.
a,
'
Motor
speed
(rpm)
Reproduced
frequency
(Hz)
|
1800 3000
| 3600 6000
2350 R35!
z = ANA AA
RED WEL Ee
SZ puy (woorjve, oh M4_g e382
= SoS gga PM 93-3,
1-7/8 MOTOR SPEED ADs
H! SPEED Sou;
3.2 PLAYBACK EQUALIZER CIRCUIT
The playback equalizer circuit is shown below.
$103 Tape Speed Switch
$104 Tape Selector Switch (Normai)
Time constants of the playback equalizer circuit at each
tape speed and selector position are as follows:
TAPE SELECTOR | ogayq, SPECIAL! | |
position NORMAL “'c.g, FeCr | METAL
TAPE (1-7/8 1PS| 120uS | 70uS 7204S | 70 us
t $—— + +
SPEED (3.3/4 1PS| 70uS 35uS , 35uS | 36uS |
Circuit Function at Each Time Constant
(1) 120 pS
S104 is Tape Selector Switch for normal position.
In the diagram, this switch is in the depressed posi-
tion, causing Q103 and Q104 to turn OFF due to
zero bias voltage. In this case, the playback time
constant is set to 120 uS by C106 and R111 ~R113.
(2) 70 pS
When the tape speed is 1-7/8 ips (4.75 cm/sec) and
S104 is OFF (S104 turns OFF when the other tape
selector switch is depressed), a bias voltage is applied
to the base of 0104 which is then turned ON. When
the tape speed is 3-3/4 ips and S104 is ON, 0104
is also ON. In either case, the playback time constant
is set to 70 pS by C106, R111 ~ R113, C114 and
R118.
(3) 35 uS
When the tape speed is 3-3/4 ips (9.5 cm/sec} and
S104 is OFF, Q103 is ON and the playback time
constant is set to 35 uS by C106, R111 ~ R113,
C111, C112 and R116.
3.3
RECORDING
CURRENT
SETTING
CIRCUIT
Recording
currents
at
each
tape
speed
and
each
position
of
the
tape
selector
switch
are
determined
by
the
follow-
ing
circuit:
$103 Tape Speed Switcn
$104 Tape Selector Normal
$105 Tape Selector Special,/Cr =
S107 Tape Selector Metal
The switch (S106) for the FeCr position is not inclujed in
the above circuit. The recording current at this position
is determined by R155 and R149 or R154 and 3148.
The resistors used to determine recording current a each
tape speed and each tape selector switch positim are
shown in the table below.
oe
TAPE SELECTOR | SPECIAL:
BECTON NORMAL | Cr0, FeCr | MEAL
- :
R155, R151 R155, R153 | R155
1-7/8 IPS |
TAPE I8PS;"R149—«| R149 niag: SS
SPEED (R154, R150/R154, R152 | R154
[33/4 1S R148 R148 Riag | R48

3.4
RECORDING
COMPENSATING
CIRCUIT
(Tape
Speed:
3-3/4
ips)
oA t
$103 Tape Speed Switch
S105 Tape Selector Switch CrO2
S107 Tape Selector Switch Metal
In
the
circuit
diagram,
C150
and
R163
are
used
for
high
range
compensation.
L104,
R168,
R169, R170,
R171
and
C154,
C155,
C156,
C157
form
a
peeking
circuit.
Peeking
frequency
and
the
amount
of
compensation
are
selected
by
the
tape
selector
switch,
R165,
R193
and
C153,
C166
are
used
for
medium
range
compensation.
The
amount
of
compensation
is
selected
by
the
tape
selector
switch
(not
available
at
‘‘Normal”’
position).
3.5
BIAS
OSCILLATOR
CIRCUIT/ERASE
OSCILLATOR
CIRCUIT
The
SD8000
has
a
bias
oscillator
circuit
and
an
erase
oscillator
circuit
to
provide
optimum
bias
and
erase
cur-
rent for the use of metal tapes.
@
The
bias
oscilator
circuit
is
driven
by
a
regulated
amp-
lifier
power
supply.
e@
The
erase
oscillator
circuit
is
driven
by
the
motor
power
supply.
The
bias
current
for
any
particular
type
of
tape
is
selectable
by
the
circuit
shown
below
(selection
of
bias
current
is
independent of tape speed).
1. Bias Oscillator Circuit
As
shown
bellow,
sy
varying
the
Q302
base
voltage,
the
bias
oscillator
circuit
operational
voltage
is
altered.
In
case
of
4-3/4
i.p.s.
(9.5
cm/sec),
do
not
adjust
by
bias
current.
Adjust
the
recording
EQ
circuit,
instead.
Inci-
dentally,
R310
is
the
bias
fine
adjust
control
on
the
front panel.
QR
<0
S23ig9
$936
ne oe
aceecnamiaes ces
| Normal CrO2 | FeCr | Metal |
——
ivihips ORAIE Gua
(4.75cm/s)i R410 ice Mae se a
aoe, pic a a i
2. Erase Oscillator Circuit
The
erase
oscillator
circuit
consists
of
Q417
and
T402.
Only
in
case
of
meta!
tapes,
R305
is
shortedto
increase
the erase current.
JsSe
SI07-@ 5102-3
Metal Rec/Hay
Switch

3-6. CONTROL CIRCUIT OPERATION
1.
General
2.
Microcomputer
The
SD8000
tape
deck
is
designed
to
have
a
wide
variety
Terminal
arrangement
(front
view)
of
functions
such
as
time
setting,
timer
setting,
program-
ming,
counter
function
and
memory
function;
all
these
are
accomplished
by
a
single
1-chip,
4-bit
microcom-
puter
element
uPD546C.
Although
the
microcomputer
performs
complex
func-
tions,
the
control
circuit
is
extremely
simple.
In
the
microcomputer,
the
memory
and
control
func-
tions
are
processed
together
at
high
speed
through
the
levels
and
timing
of
digital
pulses
available
at
input
and
output
terminals.
Since
this
instruction
manual
is
limited
in
space,
it
is
impossible
to
explain
in
detail
the
methods
of
measuring
°
“PD346C
and
checking
the
relationship
between
the
input/output
:
0701
signals
and
their
timing.
Thus,
this
manual
is
intended
only
to
cover
the
functions
of
operation
buttons
and
matrix
keys.
The
SD8000
has
various
types
of
keys
and
switches
to
provide
multiple
operations,
so
special
care
should
be
taken
when
it
is
necessary
to
check
the
cause
of
trouble
or
misoperation.
This
manual
mainly
deals
with
the
functions
of
the
SD8000
control
circuit.
Note
that
voltages
and
operat-
ing
timing
given
in
this
manual
are
for
reference
pur-
poses
and
are
subject
to
change
according
to
changes
in
power
supply
voltage
and
production
tolerance
of
CLO.1:
Clock
oscillator
LC
(external)
PE3-0:
Outputport
E3-0
components. INT: Interrupt RES: Reset PF3-0: Outputport F3-0
PA3-0: Input port A3-0 PG3-0: Outputport G3-0
PB3-0: Input port A3-0 PH3-0: Outputport H3-0
PC3-0: Input/output port C3-0 PI2-0: Outputport !2-0
PD3-0: Input/output port D3-0 TEST: Test
Fig. 2.1 Terminal arrangement (front view)
Block diagram
UP/DOWN INSTRUCTION BUS &b
PL.
ae,
COUNTER
ee
; 7
, RAM Cs An
PH. ti eee f DECODER oo
y fay
id CONTROL
a
DECODE
i) RAM [
BUFFER , oy,
STACK 2
Clo?" CLOCK 6 é
CL 0~ GENERATOR INT RES DP: Data pirtter
ALU: Operator unit
ACC: Accum} ator
PC: Progran «<ounter
Fig. 2.2 Block diagram ce rudd i
Pe:.
INTERRUPT
CONTROL.
1.0
INTERFACE
PA.-

Table 2.1 Functions of input/output signals
f Te =
j No. Signal Function
: 1 cul Clock 1 Pin 1 on clock oscillator LC
2 PCO £.)
3 PCI Input/output Fl
4 PC2 port C
5 PC3 H
Description
iape end)
of Keyboard strobe signal anc 7-segment lamp signal
T
Remarks
Not used as input
terminal.
6 INT Interrupt input Counter pulse input ‘detects
7 RES Reset input Initial reset inout
8 PDO A.
Operation button strove signal }
9 Pot input/output 2 perationucton:smeceeg Fission: arao tanal No used as input
ie port D oe Keyboard strobe signa! terminal.
: Lamo signal, PM, ERROR tamp strobe signai
12 PEO (4) SELECTOR control signal plete eee
13.
PE
Output
(3)
PROGRAM
MODE
controi
signal
lamp
signal
Jen,
14 PE2 port E (2) COUNTER MEMORY control signal “pm lamp, dis
15 PES (1) TIMER controt signal Signal’. tae
16 PFO TIMER ON LED iamo signal
17 PFI Outpur bert’ ® TIMER OFF LED iamo signal
18 PF2 me * REC LED lamp signal
19 PF3 PRG PAUSE LED 'amo signal
20 TEST Test inout Not used; connected to Vss
21 Vss Power supply +10V =1V
22 PGO TIMER ON signal
23 PGI TIMER LED iamo signat
24 PG2 Ourouriper'G RAM LED tamp signai
25 PG3 SAM LED iamo signat
26 PHO FAST \
27 PHI FR
28 pu? Output port H REW
29 PHS C/R(CUEREVIEW) | |
so i ee Oe as ape deck operation mode control
30 Plo PAUSE Toe
a Ply Output port t PLAY ‘
32 PI2 REC J
33 PAG Power frequency select sgnai
34 PAI i uRDOHEA Power sync signal
35 PA puter Program detect signai
36 PAQ Time cispiay seiect signal
37 PBO 4
38 PBI S
39 282 input port B rf Pragram signa! operation s.gnat
40 P83 VJ
41 Veg GND ov
42 CLO Clock 0 tock oscillator LC
Control signal input circuit Fig. 2.3 Control signal input circuit
W\y-—————— 9
R645 |
fr H Tt
!
Q646
Fl
———
137 a TOO
| WOO: \
-~o |; 3
nl a
AC IN
Without signai
of 10.2V)
tt +H2v : ‘
! Program With signal! (OV)
RMI5
detect signal
pelkisea
Q701
Sine wave
3.2Vpp/400 KHz
Input portA
APDS46C

The Items (1) through (8) below are basic requirements
for operating the microcomputer.
(1) Pin 1, 42
Pin 1 and pin 42 are the external terminals of the clock
oscillator LC. The internal circuits of the microcom-
puter must be synchronized with the clock signal for
proper operation. Incorrect oscillation of clock signal
will result in misoperation of the microcomputer.
The clock signal at pin 1 should be a sine wave signal
of about 3.2 Vpp/400 kHz (including a 7.6V DC com-
ponent).
(2) Pin 6
Pin 6 is the counter pulse input terminal. Pulses are
counted by the up/down counter in the microcomputer.
In the PLAY, FF or PAUSE mode, the pulses are
counted up; in the REW or REVIEW mode they are
counted down. When no counter pulses are preset at
this terminal and tape is being transported, the COUNT-
TER MEMORY will not function.
If the pulse input duration is less than 2.0 seconds, the
tape deck stops automatically.
(3) Pin 7
Pin 7 is the reset signal input terminal. When a high level
signal is applied to it, the internal circuits of the micro-
computer are reset and all functions stop.
Pin 7 becomes high level just after the power is con-
nected to the SD8000, regardless of whether the power
switch is ON or OFF. Under normal circumstances,
the voltage at Pin 7 is OV.
(4) Pin 20, 21
Pin 20 is a test terminal and Pin 21 is the power ter-
minal.
The test terminal is connected to the power supply
since it is not used. The power voltage should be +10V
t1V.
(5) Pin 33
This is an input terminal for the power frequency select
signal. The time signal of the SD8000 is obtained by
dividing the power frequency, so the frequency divider
in the microcomputer needs to be given the proper fre-
quency division ratio according to the power frequency
(50 Hz or 60 Hz).
When Pin 33 is OV (GND), the frequency division ratio
is 1/50, and when it is 10V, then the ratio is 1/60.
(6) Pin 34
This is the input terminal for the time and timer signals.
A pulse signal of 10V with the power supply frequency
should be applied to this terminal. Otherwise the cor-
rect time will not be indicated and the timer recording
function will not operate correctly.
(7) Pin 35
This is the input terminal for the program detection
signal. The programs to be played are controlled by the
applied signals. When the deck is in the playback mode,
this signal is OV for recorded portions of tape, and 10V
for blank portions between programs (where no signal
are recorded on the tape).
(8) Pin 36
Normally, a voltage of 10V is applied to this terminal.
When the voltage becomes OV, the display automatically
indicates the time.
(9) Pin 31
This is the GND terminal.

Fig. 2.4 Operation/program signal input circuit
_ 0583
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Besides the signals outlined previously, there are the In the microcomputer, these signals are synchronized
input circuits for the operation signals (PLAY, FF, etc.) with the clock signal and processed together to deter-
to select the mode of operation of the SD8000 and mine the mode of operation with the aid of the opera-
for the program setting signal (START, SKIP, etc.). tion and program switches, input and output signals and
Refer to Fig. 2.4. their timing.
Operation/indication signal output circuit
Refer to Fig. 2.5
Fig. 2.5 Control/Indication signal output circuit
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Fairs
1
(1) Tape deck operation signal
This signal is delivered from output ports H and | to
determine the mode of operation of the tape deck.
For
example,
in
the
PLAY
mode,
a
high
level
signal
is
mutput by Pin 31 and the tape deck remains in the
3 Syd, ~
Output Output Sutue Gurus Gata anor
port! portH port G portF porte portD portc
Q701 uPD546C
PLAY
mode
as
Jong
as
the
signal
is
high
level
In
the
timer
recording
(or
playback)
mode,
a
high
level
signa!
is
output
from
Pin
22
of
output
port
G.
For
the
func-
tions
of
the
circuits
in
each
operating
mode,
refer
to
Section
4
‘Tape
Operation’’

3. Circuit
This
Section
is
intended
to
explain
the
functions
of
the
motors,
solenoids
and
related
circuits.
3.1 Motor and solenoid
(1) Play motor (M001)
This
FG
servo
DC
motor
is
always
rotating
while
a
cassette
is
loaded
and
drives
the
capstan,
i.e.
the
tape,
at
a
constant
speed.
Winding
torque
is
applied
to
the
right
reel
disk
during
the
PLAY
or
REC/PLAY
mode.
(2) Reel motor (M002)
This
FG
servo
DC
motor
is
used
to
set
the
tape
in
FF,
REW
or
CUE/REVIEW
mode
(CUE
and
REVIEW
are
performed
in
the
fast
forward
and
rewind
modes
res-
pectively
while
programs
are
being
played).
tn
each
mode,
the
tape
speed
is
maintained
constant
by
means
of
the
servo
control
system
of
the
motor.
The
reel
motor
rotates
in
the
reverse
direction
when
the
deck
is
changed
from
the
fast
forward
mode
to
the
rewind
mode.
Either
the
left
or
right
reel
disk
is
driven
according
to
the
direction
of
the
motor.
The
reel
motor
is
also
used
to
remove
slack
in
tape.
(3)
Play
solenoid
(L001)
This
solenoid
functions
when
the
deck
is
in
the
PLAY
or REC/PLAY mode.
a.
The
head
base
is
lifted
and
the
head
contacts
the
tape.
b.
The
pinch
roller
contacts
the
capstan
and
the
tape
starts
running.
c.
Slight
braking
is
applied
to
the
left
reel
disk
to
pro-
vide
back
tension
to
the
tape.
d.
The
fast
forward
idler
is
set
in
the
neutral
position.
(4) Brake solenoid (L002)
This
solenoid
functions
when
the
deck
is
in
the
PLAY,
REC/PLAY,
FF,
REW,
or
CUE/REVIEW
mode.
When
it
operates,
the
eft
and
right
reel
disks
are
released
to
drive
the
tape.
(5) CUE/REV solenoid (L003)
This
solenoid
functions
when
the
deck
is
in
the
CUE/
REVIEW,
PAUSE
or
REC/PAUSE
mode.
In
the
CUE/REVIEW
mode,
the
head
base
ts
lifted
up
to
its
middle
position
to
permit
the
tape
to
contact
the
head.
In
the
PAUSE
or
REC/PLAY
mode,
the
capstan
is
released
from
the
pinch
roller
and,
at
the
same
time,
the
play
idler
is
disengaged
from
the
ree!
to
stop
tape
movement.
(6)
Recording
solenoid
(L004)
This
solenoid
functions
when
the
tape
is
in
the
REC/
PLAY
or
REC/PAUSE
mode
to
set
the
amplifier
to
the
recording
mode.
When
this
solenoid
is
inoperative,
the
amplifier
is
in
the
playback
mode.
3.2 Back-up Circuit
When
the
power
switch
is
OFF,
back-up
power
{s
Sup-
plied
to
the
microcomputer
via
T0002,
rectifier
(0419,
0424)
and
voltage
regulator
circuit
(Q421
~
Q423).
In
this
case,
the
voltage
at
Pin
36
of
Q701
is
OV,
thus
time
is
indicated
on
the
display.
During
back-up
operation,
the
programs
stored
in
memory
remain
uncleared.
3.3
Solenoid
drive
voltage
select
circuit
The
SD8000
is
equipped
with
4
solenoids.
To
ensure
proper
operation
of
these
solenoids,
a
sufficient
drive
current
is
required.
If
a
large
current
flows
into
a
solenoid,
the
solenoid
is
overheated
which,
in
turn,
increases
the
winding
resist-
ance
and
reduces
the
force
of
attraction
of
the
solenoid.
However,
once
the
solenoid
has
been
operated
with
a
large
current,
it
operates
stable
even
with
a
retatively
small
current.
The
SD8000
employs
a
solenoid
drive
voltage
select
circuit
to
select
the
operating
voltage
according
to
whether
the
solenoid
is
in
the
operating
mode
or
holding
mode.
Fig.
3.1.
and
Fig.
3.2
show
the
operating
principles
of
the
circuit
in
the
PLAY
mode.
Fig.
3-1
Solenoid
drive
voltage
select
circuit
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Fig. 3-2 Solenoid operation
PLAY
4
f
signal
:
OFF
Q529
ON
Q534
pase
eee
SS
__————_—-
aQ534
ON
OFF —
Q533
ON
__|
_____—
22V
Q532
Base
\2V
|
ev
ij
20V
Q432 Emitter lev 10V
PLAY solenoid
L001 (both ends)