Service Manuals, User Guides, Schematic Diagrams or docs for : Pioneer Audio ct_8r_9r_arp_050_0_703
<< Back | HomeMost service manuals and schematics are PDF files, so You will need Adobre Acrobat Reader to view : Acrobat Download Some of the files are DjVu format. Readers and resources available here : DjVu Resources
For the compressed files, most common are zip and rar. Please, extract files with Your favorite compression software ( WinZip, WinRAR ... ) before viewing. If a document has multiple parts, You should download all, before extracting.
Good luck. Repair on Your own risk. Make sure You know what You are doing.
Image preview - the first page of the document
>> Download ct_8r_9r_arp_050_0_703 documenatation <<
Text preview - extract from the document
(D rrloN Erl'
ORDERNO.
Shownthe photo is model CT-9R ARP-050-O
Head
Sendust
Ouar?-PLLDirectDrive/Ribbon
STEREO TAPE DECK
CASSETTE
eT-tr|trl
lI l--rr
GT-8Fl
r This servicemanualrefersto the circuit descriptions. the mechanism
For please service
discription, see
manual the CT-7R(ARP-001-0).
of
PICINEEFI ELECTFICINIG CCIFIPCIFIATICIN 4-1. Mesu.o 1-chome, Mesuno-ku, Tokyo 1s3, Jepen
U.B. PfCI\fEEFl ELECTFICX\IICB CCIFIFCIIIATICIN A5 Oxfond Dnive, Moonechie, New iJensey O7O74, u.S.A.
PICX\IEEFI ELEC?F|CIN|C aEIJFICIFE N.V. Luithagen-Haven 9, 2O3O Antwenp, Etelgium
PfC fEEFf ELECTFICTNICB A|JATF|ALIA PTY. l.rE,. 178-1A4 Eloundeny Fload, Bneeside. VictoniE 3195. Aust.alie
YZ ODEC.I98I P r i n t e di n l a p a n
1 . CIRCUIT DESCRIPTIONS
1.1 PLAYBACK FLOW
The signal picked up by the playback head is (strobe) pulse is applied to pin 1, and PM3001
amplified by the equalization amplifiers, Q1701 then starts transmitting control signals from its
and Q1703. At the same time, frequency response various output pins in accordance with which key
is corrected. was activated. (Refer to Fig. 1-3.)
The output from the equalization amplifiers is The following sections will describe the various
level-adjusted by variable resistor VR1703 and circuit operations occurring when a mode key is
then applied to Q1705. In addition to being an activated. Operations will be described for the
amplifier, Q1705 also functions to correct fre- FWD direction of travel. (Except where other-
quency response. wise specified, the pin nos. will be for PM3001.)
When normal tape is used, Q1707 wiU be ON, The DOLBY MUTE circuit shown in the signal
and the combination of Q1701, Q1703, and path diagram (Fig. 1-1) tums Q313 ON to mute all
Q1705 will set equalization to 120ps. For metal or circuik only when the position of the Dolby
CrO2 tape, Q1707 will remain OFF and equaliza- switch is changed.
tion will be 70ps.
The output from Q1705 is applied to pin 15 1. STOP Mode Key ON -Power switch ON
of IC601 (HA11226) in the Dolby circuit. Here, it Mechanism
is passed out pin 9. This output is then applied to The 16-bit serial data transmission from PD6006
pin 16 of IC602 and output from pin 9. The out- will cause pin 7 and 8 of PM3001 to go high,
put signal from IC602 passesvia the MONITOR tuming SOL L and R OFF. The mechanism will
switch to LINE OUTPUT. (A description of the thus be placed in a STOP status.
Dolby circuit will be presented later.)
Motor
1.2 RECORDINGFLOW Pin 4 and 5 will be low. and the reel motor will
The signal input to the microphone jack is first be in a STOP status.
amplified by the mic amplifier, IC1501 (NJM-
Signal Pathandothercircuits
4558D), then passedvia the INPUT selector switch
to the INPUT volume. Level is adjusted by the IN- When pin 9 is high, Q621, Q311, and Q1603 are
PUT volume and the signal is then applied to the all ON. This causes LINE OUTPUT and the head-
phone amp to be muted. If pin 11 also goes high,
flat amp IC1701 (NJM4558D). The amplifiedsignal
is then pa.ssedthrough the MPX filter and into the Q309 is tumed ON, placing the REC AMP input at
Dolby circuit. In the Dolby circuit, it is passed a ground potential. When pins 12 and 13 go low,
through Q608, IC602 (HA11226), and IC601 Q302 tums OFF, stopping the bias oscillator
circuit, and extinguishing the REC IND. Muting is
(HA11226) before input to the recording ampli-
applied to all circuits in a STOP status.
fier. From the recording amp, it is applied to the
recording head. 2. PLAY Mode Key ON
Mechanism
1.3 CONTROL CIRCUIT
Pin 7 and 8 of PM3001 go low, activating SOL L
The control circuitry of this unit is contained
and R. (Refer to the timing chart in Fig. 1-5.)
in CPU PD6006, expansion IC PM3001, and IC
This places the mechanism in the PLAY mode.
PA3010 used in the MS function. The key signals
applied to PD6006 are transmitted to PM3001 as Motor
16-bit serial data, and PM3001 then uses this data Pin 4 goes to a low level, while pin 5 is held at
to control the various circuits. a middle (M) level, causing RM R (reel-motor R)
When a mode key is activated, the 16-bit serial to start turning.
data transmission is output from pin 5 of PD6006. P06006
This is shown in Fig. 1-1. Also a clock pulse is
output from pin 7. (Data and clock pulse trans-
mission occurs once each time the key isactivated.)
The 16-bit serial data is applied to pin 3 of the
expansion IC, PM3001, and the leading edge of the 3 35)S
clock pulse is read into the shift register of PM
3001 through pin 2. t--"=
After both read events are completed, a STB Fig.1-1 PD6006
Dataoutput
MS CIRCUT
PULL-UP RESISTOR P A 3 0 10
P D6 0 0 6
(cPu )
+sv
HALF SW
FOR POWER
MS SUPPLY CT-8R
-{
sroot -ci-"
stotT --oNLY P M 3 O O l( E X P A N S
READER M-STOP - "tO----O+-O?t
i qs-orl
,- qr I
MEMORYO-JIII;
swI|MERli- _t__t
SENSING DATA sw t'-
M.REPEAT
I/B/S
\ODE rEc ) L A Y CFF
PINNO\
T- PLAY B.L.E.
35 H L H CIRCUIT
34 L H H
T- REC STB t ArJro RESEI
I c r R c uT
r
\{o.
)IN NO\ D MODEI SKIP REW
33 H L H
R
FF REC BIAS M
32 L H H MODEtr M/T
F-R SW 8/S
PREVENTION
FWD
REV REC SENSOR AUTO BLE
-rEEC MUTE
P A U S EI N D
-r- REC
REC MUTE
M U S I CR E P E A T tN0
HEAO
ffi
4 PLAY
MS MUTE
BLANK SEARCH vl
.J_ +PAUSE
PAUSE M/R IND L
INOEXSCAN REc
. FF
FF T/S IND
M S/ S K I P
_L REW
REW A/S IND REC HEAD
-gSTOP
STOP SKIP INO
.J-DIR
DIRECTION GN D
t_
Fig. 1-2 Control systemblock diagram
Pathandothercircuits
Signal
When pin 9 goes low, Q621, Q311 and Q1603
turn OFF, enabling sound to be output from
LINE OUTPUT and at the headphone jack. When
MS CIRCUT REELMOTOR
CIRCUIT pin 16 goes high, q324 tums ON and the time
constant of the blank detector circuit enters the
PLAY mode. Pins 11, pin 12 and pin 13 are in the
same state as STOP key ON.
3. FF Mode Key ON
Mechanism
PA2009 PA201c.
Pin 7 goes high and pin 8 goes low. This turns
SOL L OFF and SOL R ON, placing the mecha-
CAPSTANMOTORCIRCUIT nism in a PAUSE status.
NE
PM3OO1 (EXPANSIONIC)
Motor
Pin 4 goes low and pin 5 goes high, placing RM
L in a STOP status and causing RM R to turn.
SignalPathandothercircuits
CLOCK
| c r,,.o. Y
- e Ro N L
I Same as in the STOP status.
I I 4. REW Mode Key ON
Mechanism
J l a U TrO RRS E S E IT l l s o L .
Au o E ET Pin 7 goes high and pin 8 goes low. This turns
I crRcu r- rr
C I R C UT
I | L SOL L OFF and SOL R ON, placing the mecha-
I
nism in a PAUSE status.
Gto*'
FF REC BIAS MUTE MUTE Motor
L ---
Pin 4 goes high and pin 5 goes low. This turns
__J
MOTOR MECHANISMPATH
& RM L ON and places RM R in a STOp status.
Signal
Pathandothercircuits
^{il-:l,REAL TIME COUNTER
TAPE RUN CIRCUTT Same as in the STOP status.
SIGNAL PATH 5. REC/PLAY Mode Key ON
L IN E
OUTPUT
I Mechanism
Same as PLAY Mode Key ON.
Motor
Same as PLAY Mode Key ON.
HEADPHONES
HEAD
SignalPathandothercircuits
PHONES
AMP
rI
Rc h l
When pin 9 is low, Q621, Q311, and Q1603 are
turned OFF enabling output from LINE OUTPUT
i7
and the headphone jack. If pin 11 also goes low,
DOLBY MUTE muting is lifted from the REC AI\4P allowing the
signal to be recorded on the tape. When pins 12
and 13 go high, Q302 is turned ON activating the
bias oscillator and applying erase current to the
erase head and bias to the recording head. The
REC IND (LED) is also illuminated.
6. PAUSE Mode Key ON (in STOP status)
Mechanism
Pin 7 and 8 both go high, turning SOL L and R
OFF and placing the mechanism in a STOp status.
Motor
Same as STOP status.
SignalPathandothercircuits SignalPathandothercircuits
Same as STOP status. (The PAUSE LED is When pin 9 is high, Q621, Q311 and Q1608 are
illuminated however.) all ON. This causesLINE OUTPUT and the head-
7. PAUSE Mode Key ON (in PLAY status) phone amp to be muted. If pin 11 also goes high,
Mechanism Q309 is tumed ON, placing the REC AMP input at
a ground potential. When pins 12 goes low, QB02
Pin 7 goes high, and pin 8 goes low. This turns turns OFF, stopping the bias oscillator circuit.
SOL L OFF and SOL R ON, placing the mecha- Pin 13 goes high, causing the REC IND to illumi
nism in a PAUSE status. nate.
Motor 9. Direction Key ON (in STOP status)
Same as STOP status. Mechanism
Signal
Path Pin 7 goes low for a 275msec interval, and pin 8
Same as STOP status. (PAUSE LED is illumi- goes high. This causes SOL L to turn ON for only
nated however.) 27[msec, and since SOL R is OFF, the mechanism
goes through a direction operation from FWD-
8. REC/PLAY PAUSE Mode Key ON
STOP to REV-STOP.
Mechanism
Pin 7 goes high, and pin 8 goes low. This turns Motor
SOL L OFF and SOL R ON, placing the mecha- Same as STOP status.
nism in a PAUSE status. Signal
Pathandothercircuits
Motor Same as STOP status.
Sameas STOP status.
STOP PLAY REC,/PLAY STOP PLAY REC /PLAY
Pin FF REW PAUS PAUSE
No.
FUNCIION ' F W DI R E V F W D I R EV F w D I R E V F W O R E V FWO R E V F W D I R E V F w D I R E V F W OI R E V
RM. L L ( OFF) L n L M L IM L L L
5 RM. R L (or' n L M ML L L
HEAD SW -t L L L L L H
uooE f,
7 SOL. L HL HL L
d
(OFF) L n Hlt- HL
I SOL. R - (oFF) LH L]H L L r LH L IH
9 P B. IVUTE n
(oN) H H L L H H H
to L I N EM U T E t n H L L H L
(oN) f,
II REC MUTE H n H H L n H H
( o N)
I2 BIAS L L L L n L L
(OFF) L
t? REC L (or' L L L L L H
t4 REW IND L L n L L L L L
IOFF)
IND L rorr) H L L L L L L
t6 PLAY IND L,ora, L L H H L L L
PD oo6
H n H H n L L
t4 PAUSE IND (OFF) L
Fig. 1-3 PM3001Output stateby mode
5
Pin vo Applicable
No. Symbol Description Model
CT-gR CTR
1 E xtal Used by internal quartz oscillator
Pin 2 - GND
2 Xtal External circuit terminal f : 3.58MHz
3 RESET IN CPU reset input (effective low, normatly high)
4 M.STOP IN Memory STOP input (effective tow)
5 DATA OUT DATA output to PM3001 orrr l1___1J- rl_ g- - - - --_Sf;Lr_ o
6 NC 1234
--t Serial
T-'l r-t rr I
7 CLOCK OUT CLOCKoutput to PM3001 . ' ^ ^ u l i l A l U U A
Al U output to o o
PM3001
I NC
r[_
I STB OUT STB output to PM30O1 STB
10 SKIP OUT SKIP key scanoutput J--L _J__-L KEY
o o
11 M/l OUT MUSIC REPEAT, INDEX SCAN key scanoutput
-L- -Lr
SCAN
---1__J-- --t_r output
12 B/S OUT BLANK SEARCHkey scanoutput o
13 AUTO BLE OUT AUTO BLE startoutput [ ffi;;,pffi---- l=]-fr"
14 PAUSE ND
I OUT PAUSE indicator output (effective low)
I ndicator
o o
R E CM U T E
15
IND OUT R E C M U T E i n d i c a t o r o u t p u t ( e f f e c t i v el o w ) output
o
Ms MUTE output, PA301oMS signalMUTE output (low levelwhile reelmotor turning
16 M SM U T E OUT
during blank detectoroperation o
17 M/R IND OUT M U S I C R E P E A T i n d i c a t o r o u t p u t ( e f f e c t i v el o w l
18 r/srND OUT INDEX SCAN indicator output (effective lowl
Indicator X X
19 B/S IND OUT B L A N K S E A R C H i n d i c a t o r . o u t p u t ( e f f e c t i v el o w l output
X X
20 SKIP IND OUT SKIP indicator output (effective low)
21 GND GND o
22 DIRECTION I N DIR (directionlkey input
23 STOP IN STOP key input
24 REW IN REWkey input
25 FF IN F F key input Mode o
key
26 PAUSE IN Pause key input
input o
27 PLAY IN PLAY key input
2A REC IN REC/PLAY key input
29 R E CM U T IN REC MUTE key input o
30 RECSensor IN R E C s e n s o rs w i t c h i n p u t ( e n a b l e dt o w , d i s a b l e d h i g h )
Mechanism o
31 F-R SW IN switchinput (FWD: L; REV: H)
FWD/REVsensor SW input
32 M O D EI IN Mode \J
Mode selector switch input selector
33 M O D EI I IN SW input o
34 T.REC IN Timer RECswitchinput Timer
mode SW
35 T.PLAY IN Timer PLAY switchinput input o
36 r/B/s IN INDEX SCAN, BLANK SEARCH, SKIP key input Key
matrix
37 M.REPEAT IN MUSICREPEATkey inpur input o o
38 SENSING IN pulseinput (from PA2010pin)
Sensing J-l_l-Ll-L Reelturnins o o
39 LEADEF IN Tape leaderpulsedetectorinput (from pin 2, PA3010) n *Tape leaderdetected o
B l a n k s i g n a l i n p u t ( H l e v e l b e t w e e n s e l e c t i o ni n P L A Y , F F , R E W ; L l e v e ld u r i n g
40 MS IN
selection; H level all other timesl o
41 HALF SW IN Cassette loading switch input (Loaded: L ; Unloaded: H) o
42 VDD +5V power source o
Fig. 1-4 PD6006Pin description
Timingchart1
FWD
PIN
NO. ,,N POWERON
STOP Its STOP REW STOP P LAY STOP
PLAY /
PAUSE STOP
4 RM
L
Tr
f
R tvl R
L
Tt =
-.,r Tl
t2
1F-
i*M
6 HEAD SW
L
H
7 SOL, L
L
H
I )vL. x
L
f2 *l l* PLAY
tl
l* 'l-1
I PAUSE TI 'Ati
Zu PAUSE
gF , - Tll
*s DIR I
tl I
g6 STOP
STOP t,t
'lll
I
9 PB MUTE
H Tr
T2
-
-l f
lo LINEMUTE
L
H
T6
_l_
H
tl REC MUTE
L
t2 BIAS
L
t3 REC SW
L
ft:425mS T2:275mST!:275mS T4:225mS T5:tASmS T6:42SmS T7:42SmS Ts:325mS Te:ZgmS Tto:l25mS
F i g .1 - 5 T i m i n gc h a r to f P M 3 0 0 1 ,1
7
Timingchart2
FWD
-NooE PLAY/
PIN
N O . FUNCTIOiI\- S T OP R E C/ P L A Y STOP PAUSE REC/PAUSE R E C/ P L A Y PLAY RECl PLA Y ?EC/PAUSE S T OP
4 RM L
L
M M
f, RM. R L Jz-
t*
HEAO SW
L
r9
r Tg- T9 fe Tsr Te
7 SOL. L
H-
r
n
R SOL. R
t,
PLAY T2 |*
= PLAY
+
a
P A US E I
z; PAUSE t I -{
g< ,
DIR I
, I I
$o STOP .l*---
= STOP
I
9 PB. MUTE
H
k-! l*
rl
-lt:
I
--l_
to LINE MUTE
H
I Tz
T r8- it
-t_
tl RECMUTE
H
It'" il
t2 B IA S L
Tr
L f to-
t- t Tl
REC SW T9 t9 T9 T9 T9+ ,9
F i g . 1 - 6 T i m i n gc h a r to f P M 3 0 0 1 2
,
a
Timingchart3
FWD
---_\MO0E
PIN
\: STOP tt REW FF PLAY REW REW FF REC / PLAY REW
NO FUNCTION
H
t
4 RM. L tM Tt . Tl
L T5
lH lr
5 RM. R LT rs-H lt Fr.
M
l-rr -F T z
r
t
n irl
A HEAD SW
ili r llTg- Fl
I
7 SOL. L
H
H
Tl
ih ll
Tr
I
SOL. R Tr tl Ts
I
E PLAY I i ,l
'
PLAY I I
a I -
2P I PAUSE
i If
ll
\L
+r t
ii DIR
H; STOP I it,
STOP
I
9 PB. MUTE
n
"l h_ "t Ll
to LINEMUTE
F
."*i
L f3
l-
tl REC MUTE
H -l
t6:
I t
t2 BIAS L
t? REC SW r9 Te
L
F i g .1 - 7 T i m i n gc h a r to f p M 3 0 0 1 ,
3
Timingchart4
FWD REV FWD FWD REV FWD FWO REV FWD
PIN PT^Y / PLAY / P L A Y/
NO.
FUNCTION\ STOP STOP STOP PAUSE PAUSE PAUSE FF FF
RM L L
5 RM R tl
L
HEAD SW
L
ii
7 SOL L
H T2'
Tg
f T2=
T3-
tu T
I
I
2
d SOL R
U iil
F- PLAY - I
F
F. DIR
I
I
.1
I
I
I il- it
ii
{rr
I
= -t'r?
o',,i-j
STOP
I 'rdr
z
U
=
R- OIR
R -PAUSE_
R.PLAY _
-l
P.B MUTE
to LINE MUTE
n
tt REC MUTE
t2 B IA S
REC SW
L
D I R : 0 I R E C T I OT t : 4 2 5 m S T a : 2 7 5 m S T . : 2 7 5 m S
N T4:ZZ5mS T5:tASmS T6j42SmS T7:425mS Ts;325mS Ts:Z5mS Tro:t25mS
F i g .1 - 8 T i m i n gc h a r to f P M 3 0 0 1 , 4
r%;l F**-l
l'wo*--l
I
PLAY
I t"%*--f
Fig. 1-9 Directionoperation(in STOPstatus) Fis.1 - 1 0 D i r e c t i o n p e r a t i o n i n P A U S E ,F F a n d R E W
o (
status)
10
Timingchart5
FWD REV FWD FWD REV FWD
PIN
NO.
FUt'tCTtOt't- REW REW REW P L AY PLA Y PL A Y
RM L
f, RM L t l-Tz
I
HEAD SW L I
7 SOL. L
H Tz-
t!
L T2
Tr
l1
T2
I SOL. R L
u] i-l
Tl
ii
iir i i; il;i-
F-PLAY -
iii
U
F
s F.PAUSE-
F.DIR -
',lf
ilT
2
z R- DIR -
'{li "il
rr\
rrl i
R.PAUSE- l_
= R -PLAY _
B, MUTE
n
L a
lo LINE IVUTE
n
d
a
tl REC MUTE
BIAS L
t3 REC SW
DIR : DIRECTION
F i g . 1 - 1 1 T i m i n gc h a r to f P M 3 0 0 1 5
,
FWD-REV +
REV -FWD --*
Fig. 1-12 Directionoperation(in PLAY status)
PA3010
1 . 4 T A P E L E A D E R D E T E C T O RC I R C U I T
The tape leader detection circuit functions in
the auto-reverse mode to detect the point of
transition from the coated portion to the leader
portion of the tape. It then directs the mechanism
to reverse the direction oftravel, or places the unit
in a STOP status when this event occurs from the
fast-forward (FF) or rewind (REW) mode.
The detector uses an optical system based on an
. PHOTOTRANSISTOR
infrared LED whose emission is picked up by a
phototransistor. The circuit is activated by detect- Fig. 1-14 Tapeleader
detectorcircuit
ing a difference in the amount of light passed by
PIN
the coated portion of tape, and the amount passed NO
by the transparent leader. t6
The output from pin 16 of PA3010 is converted
to light by the LED, and passesthrough the path
shown in Fig. 1-13 to be picked up by the photo-
transistor. During tape travel, the amount of light
received by the phototransistor is quite small, so
the input level at pin 7 is held low. This causes .or 1r1-L-=----
the charge and voltage at pin 3 and 4 to also be 4 _--_!' o B
held low, presenting a low logic input to the + and
- terminals of comparator. This results in a low
output from pin 2. But as the transparent leader l-t r _
pil$es into the light path, the amount of light
picked up by the phototransistor suddenly in-
creasesthe input to pin 7. This causespin 3 to snap COATEO TAPE LEANR TAPE
high, consequently applying a high input to the +
terminal of the comparator. Output from pin 2
Fig. 1-15 Tape leader
detectorwaves
then goes high. As pin 3 goes high, the capacitor
connected to pin 4 starts charging, raising the
input level to the - terminal of the comparator. 1 . 5 E N D S E N S O RC I R C U I T
When the level of the - terminal reaches that of Since CT-9R and CT-8R are equipped with a
the + terminal, the output from the comparator tape leader detector circuit, they go into a STOP
snaps from high to low, and the output pulse status or go through a direction operation before
taken from pin 2 appears as shown in Fig. 1-1b. reaching the point where t,l-e end sensor cirucit is
CPU PD 6006 uses this output pulse to control activated, so normally the end sensor circuit will
the various mechanisms performing the mecha- not operate. However, where there is no leader on
nical functions of auto-reverse and automatic the cassette tape, or where there is an insufficient
stop. difference in the infrared transmission factor
between the coated portion and leader portion of
the tape, or in case the reel motor stops rotating
LED _ REFERENCE IN
P before the tape leader is detected, the end sensor
JN---:;:\
-l
t circuit is then activated.
Eb TAPE
.5 When the reel motor starts tuming, a sensing
1-6jJl enaser N D o w
w
nero pulse is transmitted from pin 13 of IC PA2010
n lwrrH
(used to control the reel motor) to pin 88 of
PIIOTOTRANSISTOR
PD6006. (This pulse is taken from the Hall element
and shaped into a squaxe wave by PA2010.)
Fig. 1-13 Tape leader
detectorsection When this pulse is maintained at either a low (L) or
high (H) level for a period exceeding three seconds,
PD6006 interprets that to mean the end of the
tape and thus switches to the next mode of opera-
tion.
l4
If the mechanism is in the fast-forward (FF), Consequently, when an input signal is present,
rewind (REW), or record-playback (REC/PLAY) pin 13 is at a low level, and no signal produces a
mode. the next mode entered is STOP. If it is high output. This output is used by each of the
presently in the PLAY mode and the ? reverse function operations (MS/SKIP, INDEX SCAN,
mode switch is selected, it also enters the STOP BLANK SEARCH, MUSIC REPEAT).
mode. But if ? , Q are selected,if first goesthrough
a direction operation, then into a PLAY status. PMSMUTE""' L (PIN II) ( 8 L A N K S E A R C H O P E R A T I O N) PMSMUTE',,'H( PIN I I )
9
,,1,l,..1.,,'..,,.
.[h/1.,,. ll,,r,,1.
.
ll prllrl'n --1'
_|LJ-L W mlffi ilW
lwwmm mffiilffi L
-Fr
5V 70ms+
RIGHT EEL
R
MOTORHALL
E L EM E N T
PA20to P06006
2 4vf\'
2.5V
t1 t
F i g . 1 - 1 6 E n d s e n s od i a g r a m
r
3
I t-t
1.6 BLANK DETECTOR IC PA3O1OOPERATION Fig. 1-18 Blankdetectorwaves
When the function key is placed ON, and the
reel motor starts tuming, pin 16 of PD6006 1.7 FUNCTION KEY OPERATION
goes to a low level. When pin 16 goes low, pin 11 The various functions (MS/SKIP, INDEX SCAN,
of the blank detector IC (PA3010) also goes low, BLANK SEARCH, MUSIC REPEAT) are activated
lifting MS (Music Search) muting and commenc- by placing the respective key to the ON position.
ing MS operations. The timing chart for the pulses output from pins
As MS MUTE is lifted, the signal is first ampli- 10, 11, and 12 of CPU PD6006 are shown in Fig.
fied, then applied to pin 9, and its level is deter- 1-19. As a function key is placed in the ON posi-
mined by the comparator in the next stage. Com- tion, a pulse train is input to either pin 36 or 37 of
parator output at point A is as shown in the the CPU. The CPU then determines the timing of
Fig. 1-18. the pulse train, and starts operation of the selected
This output is used to tum Tr1 ON, and this in mode accordingly.
turn allows capacitor C connected to pin !2 to
dump its charge through Tr1. Thus, pin 13 goes to
a low level. _J-----r_ _J---L
When there is no input signal present, Tr1 turns -1_I- -1J-
OFF, capacitor C starts recharging, and approxi- --l
◦ Jabse Service Manual Search 2024 ◦ Jabse Pravopis ◦ onTap.bg ◦ Other service manual resources online : Fixya ◦ eServiceinfo