Pioneer CT-8R User manual

(D
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Shown
the
photo
ismodelCT-9R ORDER
NO.
ARP
-050
-O
Ouar?-PLL
Direct
Drive/Ribbon
Sendust
Head
STEREOCASSETTE
TAPE
DECK
eT-tr|trl
lI l--rr
GT-8Fl
r Thisservicemanualrefers
to the circuitdescriptions. Forthe mechanismdiscription,
please
seeservice
manual
of theCT-7R
(ARP-001-0).
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 Printed
in lapan

1. CIRCUIT DESCRIPTIONS
1.1 PLAYBACK FLOW
The signal picked up by the playback head is
amplified by the equalization amplifiers, Q1701
and Q1703. At the sametime, frequency response
iscorrected.
The output from the equalization amplifiers is
level-adjusted by variable resistor VR1703 and
then applied to Q1705. In addition to being an
amplifier, Q1705 also functions to correct fre-
quencyresponse.
When normal tape is used, Q1707 wiU be ON,
and the combination of Q1701, Q1703, and
Q1705 will set equalizationto 120ps.For metal or
CrO2 tape, Q1707 will remain OFF and equaliza-
tion will be70ps.
The output from Q1705 is applied to pin 15
of IC601 (HA11226) in the Dolby circuit. Here,it
is passed
out pin 9. This output is then applied to
pin 16 of IC602 and output from pin 9. The out-
put signal from IC602 passes
via the MONITOR
switch to LINE OUTPUT. (A description of the
Dolby circuit will be presentedlater.)
1.2 RECORDING
FLOW
The signal input to the microphone jack is first
amplified by the mic amplifier, IC1501 (NJM-
4558D), then passed
viathe INPUT selectorswitch
to the INPUT volume. Level is adjusted by the IN-
PUT volume and the signal is then applied to the
flat amp IC1701 (NJM4558D). Theamplifiedsignal
is then pa.ssed
through the MPX filter and into the
Dolby circuit. In the Dolby circuit, it is passed
through Q608, IC602 (HA11226), and IC601
(HA11226) before input to the recording ampli-
fier. From the recording amp, it is applied to the
recording head.
1.3 CONTROL
CIRCUIT
The control circuitry of this unit is contained
in CPU PD6006, expansion IC PM3001, and IC
PA3010 used in the MS function. The key signals
applied to PD6006 are transmitted to PM3001 as
16-bit serial data, and PM3001 then usesthis data
to control the various circuits.
When a mode key is activated, the 16-bit serial
data transmission is output from pin 5 of PD6006.
This is shown in Fig. 1-1. Also a clock pulse is
output from pin 7. (Data and clock pulse trans-
mission occurs once eachtime the key isactivated.)
The 16-bit serial data is applied to pin 3 of the
expansionIC, PM3001, andthe leading
edgeof the
clock pulse is read into the shift register of PM
3001 through pin 2.
After both read events are completed, a STB
(strobe) pulse is applied to pin 1, and PM3001
then starts transmitting control signals from its
various output pins in accordance with which key
wasactivated.(Referto Fig. 1-3.)
The following sections will describe the various
circuit operations occurring when a mode key is
activated. Operations will be described for the
FWD direction of travel. (Except where other-
wise specified, the pin nos. will be for PM3001.)
The DOLBY MUTE circuit shown in the signal
path diagram(Fig. 1-1)tums Q313 ON to mute all
circuik only when the position of the Dolby
switch is changed.
1. STOPModeKeyON -Power switchON
Mechanism
The 16-bit serialdata transmission from PD6006
will cause pin 7 and 8 of PM3001 to go high,
tuming SOL L and R OFF. The mechanism will
thus be placed in a STOPstatus.
Motor
Pin 4 and 5 will be low. and the reel motor will
bein a STOP
status.
Signal
Pathandothercircuits
When pin 9 ishigh, Q621, Q311, and Q1603 are
all ON. This causes
LINE OUTPUT and the head-
phone amp to be muted. If pin 11 alsogoes
high,
Q309 is tumed ON, placingthe REC AMP input at
a ground potential. When pins 12 and 13 go low,
Q302 tums OFF, stopping the bias oscillator
circuit, and extinguishing the REC IND. Muting is
applied to all circuits in a STOP status.
2. PLAY Mode Key ON
Mechanism
Pin 7 and 8 of PM3001 golow, activatingSOL L
and R. (Refer to the timing chart in Fig. 1-5.)
This places the mechanism in the PLAY mode.
Motor
Pin 4 goesto a low level, while pin 5 is held at
a middle (M) level, causingRM R (reel-motor R)
to start turning.
P06006
t--"=
Fig.1-1 PD6006
Dataoutput
3 35)S

MS CIRCUT
PULL-UP
RESISTOR
PM3OOl
(EXPANSIO
t ArJro
RESEI
I crRcurT
REW R
FF RECBIASM
MUSIC
REPEAT
PREVENTION
FWD
REV
-rEEC MUTE
-r- REC
4 PLAY
+PAUSE
. FF
_L REW
-gSTOP
.J-DIR
HEAO
ffi
vl
L REc
BLANK SEARCH
.J_
INOEXSCAN
MS
/SKIP
REC
HEAD
t_
PA301
0
\ODE
PINNO\ rEc)LAY CFF
35 HLH
34 L H H
PD
6006
(
cPu
) +sv
FORPOWER
SUPPLY CT-8R
sroot stotT --oNLY -{ -ci-" i qs-orl
-€ "tO----O+-O?t ,-€ qr I
MEMORYO-JIII;
swI|MERli- _t__t
sw t'-
HALF SW
MS
READER
SENSING
M.
REPEAT
I/B/S
M
-STOP
DATA
T- PLAY
T-
REC STB
MODE
I SKI P
MODE
tr M/T
F-R SW 8/S
REC
SENSOR AUTO
BLE
PAUSE
IND
RECMUTE
tN0
MS MUTE
PAUSE M
/R IND
FF T
/S IND
REW A/S IND
STOP SKIP INO
DIRECTION GND
B.L.E.
CIRC
U
IT
\{o.
)IN
NO\ D
33 HLH
32 LHH
Fig.1-2 Controlsystemblock
diagram

MS CIRCUT REEL
MOTOR
CIRCUIT
J lauroRESETlI lsoL.
I crRcurr r- | L
I
Gto*'
FF REC BIAS MUTE MUTE
AUTO
RESET
CIRCUIT
HEAD
PHONES
AMP
L
--- __J
MOTOR
& MECHANISM
PATH
REAL TIME COUNTER
TAPE RUN CIRCUTT
Signal
Path
andothercircuits
When pin 9 goes
low, Q621, Q311 and Q1603
turn OFF, enabling sound to be output from
LINE OUTPUT and at the headphonejack. When
pin 16 goes high, q324 tums ON and the time
constant of the blank detector circuit enters the
PLAY mode. Pins 11, pin 12 andpin 13 arein the
same
stateasSTOPkey ON.
3. FF ModeKey ON
Mechanism
Pin 7 goeshigh and pin 8 goes
low. This turns
SOL L OFF and SOL R ON, placing the mecha-
nism in aPAUSE status.
Motor
Pin 4 goeslow and pin 5 goes
high, placing RM
L in a STOP status and causing RM R to turn.
Signal
Path
andother
circuits
Same
asin the STOPstatus.
4. REW
ModeKey ON
Mechanism
Pin 7 goeshigh and pin 8 goes
low. This turns
SOL L OFF and SOL R ON, placing the mecha-
nism in aPAUSE status.
Motor
Pin 4 goes high and pin 5 goes
low. This turns
RM L ON and places
RM R in a STOp status.
SignalPath
andother
circuits
Same
asin the STOPstatus.
5. REC/PLAY ModeKey ON
Mechanism
Same
asPLAY Mode Key ON.
Motor
Same
as
PLAY Mode Key ON.
Signal
Path
and
othercircuits
Whenpin 9 is low, Q621, Q311,
and
Q1603
are
turned OFF enabling output from LINE OUTPUT
and the headphone
jack. If pin 11 alsogoes
low,
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) isalso
illuminated.
6. PAUSE
Mode KeyON (inSTOPstatus)
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
STOPstatus.
PA2009 PA201c.
PM3OO1
(EXPANSION
IC)
CLOCK
CAPSTAN
MOTOR
CIRCUIT
NE
| ,,.o. I
I cr-eR
oNLY
I
^
{
il-:l,
SIGNAL
PATH
LI
NE
OUTPUT I
HEADPHONES
rI
chl
i7
R
DOLBY MUTE

Signal
Path
and
othercircuits
Same as STOP status. (The PAUSE LED is
illuminated however.)
7. PAUSE
ModeKey ON (in PLAY status)
Mechanism
Pin 7 goes
high, and pin 8 goes
low. This turns
SOL L OFF and SOL R ON, placing the mecha-
nism in aPAUSE status.
Motor
SameasSTOPstatus.
SignalPath
Same as STOP status. (PAUSE LED is illumi-
natedhowever.)
8. REC/PLAY PAUSE
ModeKey ON
Mechanism
Pin 7 goes
high, and pin 8 goes
low. This turns
SOL L OFF and SOL R ON, placing the mecha-
nismin aPAUSE status.
Motor
Sameas
STOPstatus.
Signal
Path
andother
circuits
When
pin 9 is high, Q621, Q311 and
Q1608are
all ON. This causes
LINE OUTPUT and the head-
phone amp to be muted. If pin 11 alsogoes
high,
Q309 is tumed ON, placingthe REC AMP input at
a ground potential. When pins 12 goes
low, QB02
turns OFF, stopping the bias oscillator circuit.
Pin 13 goes high, causing the REC IND to illumi
nate.
9. DirectionKeyON (inSTOP
status)
Mechanism
Pin 7 goes
low for a 275msec
interval, andpin 8
goeshigh. This causes
SOL L to turn ON for only
27[msec, and sinceSOL R isOFF, the mechanism
goes through a direction operation from FWD-
STOPto REV-STOP.
Motor
SameasSTOPstatus.
SignalPath
and
othercircuits
Sameas
STOP
status.
Pin
No. FUNCIION '
STOP FF REW PLAY REC,/PLAY STOP
PAUS€ PLAY REC/PLAY
PAUSE
FWD
IREV FWD IRE
VFwD
I
REV FWO REV FWO REV FWD
I
REV FwD
I
REV FWO
I
REV
RM. LL(
OFF) L n LML IM LLL
5RM. RL (or' nLMML LL
HEAD SW - tuooE LLLf, LLH
7SOL. Ld(OFF) HL HL LLnHlt- HL
ISOL. R- (oFF) LH L]H LL r LH L IH
9PB. IVUTE n(oN) HHLLHH H
to LINEMUTE t (oN) nHLLf, HL
II REC MUTE H(oN
)nHHLnHH
I2 BIAS L(OFF) LLLnLLL
t? REC L (or' LLLLLH
t4 REW IND LIOFF) LnLLLLL
IND L rorr) HLLLLLL
t6 PLAY IND L,ora, LLHHLLL
PD oo6 H(OFF
)nHHnLLL
t4 PAUSE IND
5
Fig.
1-3 PM3001
Output
statebymode

Pin
No. Symbol vo Description Applicable
Model
CT-gR CT€R
1E xtal Usedby internal quartz oscillator
External
circuit terminalf : 3.58MHz Pin
2 - GND
2Xtal
3RESET IN CPU resetinput (effective low, normatly high)
4M.STOP IN Memory STOP input (effective tow)
5DATA OUT DATA outputto PM3001 orrr l1___1J- rl_g
- - - - --_Sf;Lr_
1234
--t T-'l r-t rr I
.'^^ulilAlAlA
UUU
Serial
output to
PM3001
o
6NC
7CLOCK OUT CLOCKoutput
to PM3001 oo
INC
ISTB OUT STBoutputto PM30O1 r[_
STB
10 SKIP OUT SKIPkey
scanoutput J--L _J__-L
-L- -Lr
---1__J-- --t_r KEY
SCAN
output
oo
11 M/l OUT MUSIC REPEAT, INDEX SCAN key scanoutput
12 B/S OUT BLANK
SEARCHkey
scan
output o
13 AUTO
BLE OUT AUTO
BLE
start
output [ ffi;;,pffi---- l=]-fr"
14 PAUSE
IND OUT PAUSE indicator output (effective low) Indicator
output
oo
15 REC
MUTE
IND OUT REC MUTE indicator
output (effective
low) o
16 MSMUTE OUT MsMUTEoutput,PA301o
MS
signal
MUTE
output
(low
level
while
reelmotor
turning
during
blank
detector
operation o
17 M/RIND OUT MUSIC REPEAT indicator
output (effective
lowl
Indicator
output
18 r/s
rND OUT INDEX SCAN indicator output (effective lowl XX
19 B/SIND OUT BLANK SEARCH indicator.output (effective
lowl X X
20 SKIPIND OUT SKIP indicator output (effective low)
21 GND GND o
22 DIRECTION IN DIR(directionl
key
input
Mode
key
input
23 STOP IN STOP key input
24 REW IN REW
keyinput
25 FF IN FFkey input o
26 PAUSE IN Pause
key input o
27 PLAY IN PLAY key input
2A REC IN REC/PLAY key input
29 REC
MUT IN RECMUTE
key
input o
30 REC
Sensor IN RECsensor
switch input (enabled
tow, disabled
high) Mechanism
SWinput o
31 F-R
SW IN FWD/REV
sensor
switch
input
(FWD:
L; REV:H)
32 MODE
IIN Mode selectorswitch input Mode
selector
SWinput
\J
33 MODE
II IN o
34 T.REC IN TimerREC
switchinput Timer
modeSW
input
35 T.PLAY IN Timer
PLAY
switchinput o
36 r/B/s IN INDEX SCAN,
BLANK SEARCH,
SKIP
key
input Key
matrix
input
37 M.REPEAT IN MUSICREPEAT
key
inpur oo
38 SENSING IN Sensing
pulse
input
(from
PA2010
pin) J-l_l-Ll-L Reelturnins oo
39 LEADEF IN Tape
leader
pulse
detector
input (frompin 2, PA3010) n *Tape leader
detected o
40 MS IN Blank
signalinput (H level
between
selectionin PLAY, FF, REW; L level
during
selection; H levelall other timesl o
41 HALF
SW IN Cassetteloading switch input (Loaded: L ; Unloaded: H) o
42 VDD +5V power
source o
Fig.
1-4 PD6006
Pin
description

Timing
chart
1FWD
PIN
NO. ,,N POWER
ON
STOP Its STOP REW STOP P
LAY STOP PLAY
/
PAUSE STOP
4RM
L
Tr f
Rtvl RL
Tt
=-.,r Tl
t2 i*M
1F-
6HEAD SW L
7SOL, L L
H
I)vL. x L
H
I
Zu
gF
*s
g6
PAUSE
DIR
STOP
tl
STOP
l*
,
I
PAUSE -
f2
TI
*l l* PLAY
'l-1
'Ati
Tll
tl I
t,t I
'lll
9P
B MUTE L
-f-l
HTr
T2
T6
lo LINEMUTE _l_
H
tl REC MUTE L
H
t2 BIAS L
t3 REC SW L
ft:425mS T2:275mST!:275mS T4:225mS T5:tASmS T6:42SmST7:42SmS Ts:325mS Te:ZgmS Tto:l25mS
Fig.
1-5 TimingchartofPM3001,
1
7

Timingchart2 FWD
PIN
NO.
-NooE
FUNCTIOiI\- STO
PREC
/ PLAY STOP PLAY
/
PAUSE REC/PAUSE REC/PLAY PLAY RECl PLAY ?EC/PAUSE STOP
4RM LL
f, RM. RL Jz-
M
t* M
HEAO SW Lr9 T9 Tsr
rTg- fe Te
7SOL. Lr
H-
RSOL. R n
=
z;
g<
$o
=
PLAY
PAUSE
DIR
STOP STOP
t,
+
I
PLAY
PAU
SE
t
,
,
T2 |* -{
I
aI
I
I
.l*---
I
9PB. MUTE k-! l*
rl I
-l
t:
H
to LINEMUTE --l_ ITz T r8-
it
H
tl RECMUTE -t_ It'" il
H
t2 BI
AS LTr Lf to- t
t- Tl
REC SW T9 T9 T9+ t9 T9 ,9
Fig.
1-6 TimingchartofPM3001,
2
a

Timing
chart
3FWD
PIN
NO
---_\MO0E
FUNCTION
\: STOP tt REW FF PLAY REW REW FF REC
/ PLAY REW
4RM. LLtM Tt . Tl
H
T5 t
5RM. R LT lH
t rs-Hlr M
lt Fr. lr-
r-r FTz
AHEAD SW irl
r llTg-
nili FlI
7SOL. Lih
HTl Tr
SOL. R Tr ll
tl Ts I
I
H
E
a
2P
ii
H;
PLAY
DIR
STOP STOP
I
I PAUSE il
', ll
if
I
I
PLAY I
I
\L I
-
+r
it, t
I
9P
B. MUTE n"l h_ "tLl
to LINEMUTE l-
F."*i
Lf3
tl REC MUTE H-l t6: It
t2 BIAS L
t? REC SW Lr9 Te
Fig.
1-7 Timing
chart
ofpM3001, 3

PIN
NO. FUNCTION\
FWD
STOP
REV
STOP
FWD
STOP
FWD
PT^Y
/
PAUSE
REV
PLAY
/
PAUSE
FWD
PLAY
/
PAUSE
FWO
FF
REV FWD
FF
RM LL
5RM RLtl
HEAD SW Lii
7SOL Ltu I
I2
H T2'
Tg fT2=
T3- T
dSOL R Uiil
F
=
I
z
U
=
F- PLAY -
F. DIR
STOP
R-
OIR
R
-PAUSE_
R.PLAY _
I
I
I
I
-t .1
I
I
I
{rr il- it
ii
'r? o',,i-j 'rdr -l
P.B MUTE
to LINE MUTE
tt REC
MUTE n
t2 BIAS
REC SW L
Timing
chart4
DIR:0IRECTION
Tt:425mS Ta:275mS
T.:275mS T4:ZZ5mS T5:tASmS T6j42SmS
T7:425mS Ts;325mS Ts:Z5mS Tro:t25mS
Fig.
1-8 Timing chart
ofPM3001,4
1-10 Direction operation
status)
r%;l
l'wo*--l
I PLAY I
F**-l
t"%*--f
10
Fig.
1-9 Direction
operation
(in
STOPstatus) Fis. (in
PAUSE,
FF
andREW

Timing
chart
5
Fig.
1-11 Timingchart
ofPM3001, 5
FWD-REV +
REV -FWD --*
PIN
NO. FUt'tCTtOt't-
FWD
REW
REV
REW
FWD
REW
FWD
PLAY
REV
PLAY
FWD
P
LAY
RM L
f, RM Lt l-Tz
HEAD SW LI
I
7SOL. LLT2
Tr l1
T2
H Tz-
t!
ISOL. RLu] i-l Tl ii
U
F
s
2
z
=
F-PLAY -
F.PAUSE-
F.DIR -
R-
DIR -
R.PAUSE-
R
-PLAY _iir i
i;
"il iii il;i-
',
lf
ilT
'{li rr\ i
rrl
l_
B, MUTE La
n
lo LINE IVUTE a
n
tl REC
MUTE d
BIAS L
t3 REC SW
DIR : DIRECTION
Fig.
1-12 Direction
operation
(in
PLAYstatus)

PA3010
1.4 TAPE LEADER DETECTOR
CIRCUIT
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 reversethe direction oftravel, or placesthe unit
in a STOP status when this event occurs from the
fast-forward (FF) or rewind (REW) mode.
The detector usesan optical system based
on an
infrared LED whose emission is picked up by a
phototransistor. The circuit is activated by detect-
ing a difference in the amount of light passed
by
the coated portion of tape, and the amount passed
by the transparent leader.
The output from pin 16 of PA3010 is converted
to light by the LED, and passes
through 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
the charge and voltage at pin 3 and 4 to also be
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
pil$es into the light path, the amount of light
picked up by the phototransistor suddenly in-
creases
the input to pin 7. This causes
pin 3 to snap
high, consequently applying a high input to the +
terminal of the comparator. Output from pin 2
then goes high. As pin 3 goeshigh, the capacitor
connected to pin 4 starts charging, raising the
input level to the - terminal of the comparator.
When the level of the - terminal reaches that of
the + terminal, the output from the comparator
snaps from high to low, and the output pulse
taken from pin 2 appears as shown in Fig. 1-1b.
CPU PD 6006 usesthis output pulse to control
the various mechanisms performing the mecha-
nical functions of auto-reverse and automatic
stop.
LED _ REFERENCE PIN
JN---:;:\
-l t
Eb TAPE
.5
1-6jJl enasenero
n lwrrH
wrNDow
PIIOTOTRANSISTOR
Fig.
1-13 Tape leader
detector
section
. PHOTOTRANSISTOR
Fig.1-14 Tapeleader
detectorcircuit
PIN
NO
t6
4.or 1r1-L-=----
_--_!' o B
l-tr_
COATEOTAPE LEANR TAPE
Fig.
1-1
5 Tapeleaderdetector
waves
1.5 END SENSOR
CIRCUIT
Since CT-9R and CT-8R are equipped with a
tape leader detector circuit, they go into a STOP
status or go through a direction operation before
reaching the point where t,l-eend sensorcirucit is
activated, so normally the end sensor circuit will
not operate. However, where there is no leader on
the cassettetape, or where there is an insufficient
difference in the infrared transmission factor
between the coated portion and leader portion of
the tape, or in case the reel motor stops rotating
before the tape leader is detected, the end sensor
circuit is then activated.
When the reel motor starts tuming, a sensing
pulse is transmitted from pin 13 of IC PA2010
(used to control the reel motor) to pin 88 of
PD6006. (This pulse is taken from the Hall element
and shaped into a squaxe wave by PA2010.)
When this pulse is maintained at either a low (L) or
high (H) level for aperiod exceedingthree 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),
rewind (REW), or record-playback (REC/PLAY)
mode. the next mode entered is STOP. If it is
presently in the PLAY mode and the ? reverse
mode switch is selected, it also enters the STOP
mode. But if ? ,Q areselected,if first goes
through
a direction operation, then into a PLAY status.
_|LJ-L
RIGHT
REEL
MOTOR
HALL
ELEMENT PA20to P06006
Fig.
1-16 End
sensor
diagram
1.6 BLANK DETECTOR IC PA3O1O
OPERATION
When the function key is placed ON, and the
reel motor starts tuming, pin 16 of PD6006
goes
to a low level. When pin 16 goes low, pin 11
of the blank detector IC (PA3010) also goes
low,
lifting MS (Music Search) muting and commenc-
ing MS operations.
As MS MUTE is lifted, the signal is first ampli-
fied, then applied to pin 9, and its level is deter-
mined by the comparator in the next stage.Com-
parator output at point A is as shown in the
Fig.1-18.
This output is used to tum Tr1 ON, and this in
turn allows capacitor C connected to pin !2 to
dump its charge through Tr1. Thus, pin 13 goes to
alow level.
When there is no input signal present, Tr1 turns
OFF, capacitor C starts recharging, and approxi-
mately 7Omseclater, a high level is output from
pin 13.
Consequently, when an input signal is present,
pin 13 is at a low level, and no signal produces a
high output. This output is used by each of the
function operations (MS/SKIP, INDEX SCAN,
BLANK SEARCH,
MUSICREPEAT).
PMSMUTE""' L (PIN II) (8LANK SEARCH OPERATION
)PMS
MUTE
',,'H
(
PIN
II)
9,,1,l,..1.,,'..,,..[h/1.,,. ll,,r,,1..
ll prllrl'n --1'
Wmlffi ilW
lwwmm mffiilffi L
2
5V 70ms+
-Fr
4vf\' t1 t
2.5V
3I t-t
Fig.
1-18 Blankdetector
waves
1.7 FUNCTIONKEY OPERATION
The variousfunctions (MS/SKIP, INDEX SCAN,
BLANK SEARCH, MUSIC REPEAT) areactivated
by placing the respective key to the ON position.
The timing chart for the pulsesoutput from pins
10, 11, and 12 of CPU PD6006 are shown in Fig.
1-19. As a function key is placed in the ON posi-
tion, a pulse train is input to either pin 36 or 37 of
the CPU. The CPU then determines the timing of
the pulse train, and starts operation of the selected
mode accordingly.
_J-----r_ _J---L
-1_I- -1J-
--l f
-l r !e-l
i- c+
-LJ- -Lr
Fis.
1-19
A=57!S A=AOIS. Cr27oS
Functionkeydiagram
1. MS/SKIPOperation
When the MS/SKIP Key is placed ON, the FF
( >> ) key is activated, and when the beginning of
a music selection is located, pin 13 of PA3010
drops from high to low. The trailing edge of the
pulse effecting the level drop at the PD6006 pin
sets the REWIND mode and rewinds the tape
back to the beginning of the selection, and enters
thePLAY mode.
Fig.1-17 Blankdetector
circuit

At the end of the selection, if the unrecorded
section of the tape (functioning to change the
output from pin 13 from low to high) holds the
level continuously high for over 8 seconds,
PD6006
then selects
the FF mode, continuing in that mode
until the beginning of the next selection drops
the level at pin 13 low. It then rewinds ( << )
back out to the beginning of the selection, and
enters
the PLAY mode.
After this 7 seconds has elapsed, it once again
retums to the FF or REW mode and cycles
through another search operation until all selec-
tions on the tape arethus indexed.
If the tape should end while the unit is in FWD
FF, or REV REW, either the STOP
statuswould be
entered, or a direction operation would allow
searchto continue, depending on the reversemode
switch setting.
When in INDEX SCAN operation, REW KEy
(FF KEY in REV direction)is placed
ON,INDEX
SCAN is operated in REW mode as shown in Fig.
r-2t.
3. BLANK SEARCH Operation
When the BLANK SEARCH key is placed ON,
if the unit is operating in the FWD direction, the
searchis started in the FF ( >> ) mode; if operat-
ing in REV, it is started in the REW ( << ) mode.
When input to the blank detector (output by pin
13 of PA3010) is held high for 8 seconds,
or when
the tape end sensoris detected, the present direc-
tion of travel is reversed, and the tape returns to
the position where input to the blank detector
snappedfrom high to low.
From this position, the unit reenters the PLAY
mode until a point is reached where the input at
the blank detector is maintained at a continuously
high level for 4 seconds.
It then goes
into a STOp
status,completing the operation.
As shown in Fig. L-22 (3), in caseof the un-
recorded tape, the tape retums to the tape end in
REW mode after the search had been done for 8
seconds
in FF mode-
When detecting the tape end, the tape travels
the leader tape portion for 0.8 seconds in FF
mode andthen goes
into a STOP.
i.- e sec -l
IAPE
ENO
l i I D.
Fig.
1-20 MS/SKIP
operation
2. INDEX SCANOperation
When INDEX SCAN is activated, if the unit is
operating in the FWD direction, the FF ( >> )
modeisentered;
if in REV, REW ( << ) isentered.
The unit then cycles through a search operation
to locate the beginning of a selection, then goes
into the PLAY mode. Playback of the selection
starts and continues for the 7 secondsthat pin 18
of PA3010 is held low.
REW
REWKEYON
D
I
R
E
c
T
I
N
LEADEFi PLAY
r8 sec
=
Fig.1-21 INDEX
SCAN
operation Fig.
1-22 BLANKSEARCH
operation

4. MUSIC
REPEATOperation
When the MUSIC REPEAT key is placed ON
while the unit is presently in the PLAY status,
the present music selection (or the next if un-
recorded tape selections) continues to completion,
then the output from pin 13 of PA3010 goes
from
Iow to high. After the output of pin 13 has been
held high f.ot 2.5 seconds,the unit returns to the
beginning of that selection and repeatsplayback.
This operation may be repeated for the same
selection for up to 8 times, after which MUSIC
REPEAT is cleared and a STOP status entered. out
put
The STOP status will also be entered in casethe t
end sensoris activated.
Fig.
1-23 MUSICREPEAToperation
1.8 DOLBY NR PROCESSOR
The CT-9R and CT-8R both feature type B and
type C Dolby NR processors.
The type C Dolby NR system enablesnoise to
be reduced by up to 20dB at frequencies above
7l<Ilz. The basic operating principles are the same
as for the type B Dolby NR system, the major
difference lying in the use of two separate pro-
cessor stages (a high level stage and a low level
stage connected in series). Switching to a type
B Dolby NR processoralsoenables
Wpe B encoded
tapes to be played. Block diagxamsfor encoding
and decoding operations are outlined in Ftgs.
L-25 and L-26 respectively. The corresponding
input/output frequency responsecurves areshown
in Fig. 1-24.
The REC srgnal is passed through a spectral
skewing circuit (see Fig. 1-25) which is an LC
resonator with an for at 2OWlz, and designed to
prevent low to mid-range decoding error (high
levelleakage)due to high level signals.
The REC signal is then applied to the lst
processor stage
(high level stage)where it is divided
rnto 2 signals,the main signalbeing passed
directly
to adder A, while the main signal is passed via
SCF-1 (side chain filter), arnplifier B and over-
shoot suppressor C before being applied to adder
A where the main and sub signalsarerecombined.
15
......* Input
Fig.
1-24 InpuVOutputcharacteristic
In addition, the amplifier B output is applied to
rectifier E (non-linear integrating type) via ampli
fier D, the rectified output being applied to VCR-1
(voltage control resistor) of SCF-1. This SCF is a
variable high-pass filter where the frequency
response is varied according to the VCR value.
The VCR value is increased under low level con-
ditions, and the SCF-1 tumover frequency is
determined by CURI. The level of the adder A
output will thus be 10dB higher than the main
signal level (around 1.5kHz), and the dynamic
range will be contracted. The VCR value will drop
when the VCR control voltage exceeds the
threshold value, and the SCF-1 turnover frequency
will be increased by C2lC!lR2lVCR-1, thereby
attenuating low to mid-range signals in the sub-
signal. And since the sub to main signal ratio is
lower at higher input signal frequencies, the
degree of dynamic range conhaction is smaller.
The adder A output is applied to the 2nd
processor stage (low level stage) where the signal
whose dynamic range was compressed in the lst
compressor stage is added. In order to further
compress the dynamic range in this 2nd processor
stage, the threshold level of the 2nd processor
VCR-2 control voltage is set below the corespond-
ing level of the 1st processor stage. The 2nd
processor stage also includes an anti-saturation
circuit R. The purlpose of this circuit is to effect
the same improvements as the spectral skewing
circuit.
During playback (se Fig. t-26), the samebasic
circuitry is usedasin recording mode, but with the
1st and 2nd processor stages
in the reverseorder.
Since the circuit starts from the output of the
inverter (sub-signal output), a negative feedback
loop is formed with the sub-signal
being subtracted

from the main signalin adder A'. And sincethe sub-
signalpath operation is exactly the sameasduring
recording mode, the decoding and encoding
characteristics complement each other. Further-
more, the anti-saturation P and spectral de-skewing
characteristics during decoding are the exact
RECIN
P.B.
IN
opposite of the conesponding characteristics
during encoding. Consequently, a flat frequency
response is maintained at all levels after all phases
of the encoding and decoding opperations are
completed.
REC
OUT
PB.
OUT
Spectral
de-skewing
lst processor(high levet
stagol 2nd processor (low level stagel
Inverter ii salgelenR
I Inverter | | saruralton Ft
i Adder A r\ : I l-l Adder A'
Overchoot
Amp. B suppressor
C
rl
ll
tl
tl
gl
rl
tl
tl
ii
tl
ll
tl
tl
rl
FiS.
t-ZS Blockdiagramfor encoding operation
2nd procesor (low lanel stagel lst processor(high lovelstagel
Adder A' lnverter Anti-
saturation PAdder A
Overshoot Overshoot
suppressor
C Amp. I
C' Amp.B'
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
16
scF-
|
R4 c6 Overshoot
Amp. B' suppressor
g):.,!- ,thln
L=
iJn""tirier E,
Amp.D,
scF-2 scF-|
i- tl-l[}r*
t+
Amp.D' Rectifier E'l +
J || -l*L
;"".iri"reE
Fig.
1-26 Blockdiagram
for decodingoperation

1.9 AUTO BLE CIRCUIT
Auto BLE provides the function of setting bias,
recording level and equalization to obtain the ideal
recording characteristics exhibited by the various
type formulations. Operation is fully automatic.
When the AUTO key is pressed,
a signal is trans-
mitted from PD4010 to control IC PD6006 in
initiating mechanism operation and coarse-adjust
recording level. It then shifts to bias adjustment.
Bias is set by detecting the ideal current, deter-
mined by subjecting the lkHz tone oscillator signal
to record/playback at 16 step levels of intensity
and selecting which of the 16 bias strengths is best.
The resistanceof the biascircuit is set accordingly.
This adjustment cycle may be repeated up to
four times. Then after equalization has been set,
SIGNAL PATH
}IEAD
the tape is rewound to the starting position. The
complete adjustment process requires from 10 to
20 seconds.
In caseone of the adjustments is impossible for
AUTO BLE to make, it is automatically disabled.
The tape is then rewound and standard values are
set.
The detection method used for each value
adjustment consists of passing
the record/playbaek
signal through the Lch and Rch rectifier circuits
and comparing them (with comparators) with an
analog voltage obtained from a CPU digital sgnal
passedthrough the D/A converter. These circuits
arecontainedin PM9001.
MECHANISMPATH
CLEAR
LINE
OUTPUT
17
CONTROLPATH
PM900 I
n. osc
Fig.'l-27 B.L.E.circuitblockdiagram

1.10 REAL TIME COUNTER
The CT-9R uses
a HaIl element sensor
to detect
the rotational speed
of the reel carrier, and inputs a
pulsesignalto PD6008 for use
by the tape counter
and real time counter.
TapeCounter Function
o Tape
counter
setto "0000" atthetime
power
is
turned
oN.
1. When the power switch isturned ON, e1206 is
ON during the 100ms interval required for
cunent to pass
through+B,R1214, R121b and
charge
C1218.
2. Q1206 being ON alsoturns qL2O7 ON, andits
collector is at alow level.
3. This low signal is applied to pin B of IC904
(PD6008). Pin 13 thru 18 of IC904 are high,
andpin 19 islow.
4. This output is passedto LED 1101 via the
inverting amplifier of ICg0b (Mb4b1?p),
setting
the displayto "0000,'.
5. Thus, the tape counter restarts
from .,0000" at
the time power is applied to the unit.
Fig.
1-28 Tapecounter
function
'no
16r)-l
l\<tYl
4.
5.
o Tapecounter
increment/decrement
"nnnn"
1. As shown in Fig. L-29, the Hallvoltage genera-
ted by the Hall element (H252: HB) built into
the right reel carrier is applied to pins 16 and
17 of lC2O2 (PA2010) and is output from pin
13.
2. This output is applied to pin 32 of. IC904
(PD6008).
3. At the same
time, the voltage generatedby Hall
element (H251 : HA) is applied to pins 5 and
6 of IC903 (NJM2903) and is output from
pin 7.
This output is applied to pin 30 of IC904.
Signal input to pins 30 and 32 causesegment
data to be transmitted by pins 13 thru 1g
(active high), and digital data to be transmitted
by pins 26 thru 29. This changes
the numerical
display of the tape counter.
6. When the tape is traveling in the FWD direc-
tion, the pulse shown in Fig. 1-29 is applied
with each tum of the reel, causingthe counter
to increase.
7. When the tape is traveling in the REV direc-
tion, the pulse shown in Fig. 1-29 is applied
with each tum of the reel, causingthe counter
to decrease.
too
coLUMN
(
UNITS
)
IC9o4
PrN
30rNPUl| L_t LJ L
rcao4 f--'l fi --.1
',1u,i3.,
J Ll l_J L
COUNTER
INCREMENT
lC904
PIN 30
INPUT
IC904
PIN
32
INPUT
ffi
m
to2
coLuMN
(HUNORES
)
ro!coLUMlt
(
rHousaNDS
)
ROTOR
MAGNET AND HR
HALL ELEMENT
RELATIONSH
IP
7C202
PIN
13
OUTPUT
4- PULL-UP
R€SISTOR
"ula=-ol
JI-I]JA
18
Fig.
1-29 Tapecounter
increment/decrement"nnnn"

a Counterreset
1. When the counter reset switch (S1101) is
placed ON, pin 41 of IC904 (PD6008) dropsto
a low level, and pins 13 thru 18 go high, with
pin 19low.
2. Thus, when 51101 is held down, the tape
counter unconditionally resets the counter to
"0000". However, real time operations by
IC904 continues, and when S1101 is released,
the counter will once again indicate real time.
Real
Time CounterFunction
When the Counter/Mode switch (S1102) is
placed ON, the counter can be switched to eigher
tape counter or real time counter operation.
1. Placing 51102 ON causespin 40 of IC904
(PD6008)
to drop low.
2. This causesa high output from pin 20 to turn
Q921 ON, illuminating the LED1101 dot
indicator.
3. If the tape is traveling, voltage generatedby the
right reel carrier Hall element (HA: H251) is
input to pins 5 and 6 of IC903 (NJM2903),
and output is obtained from pin 7.
4. At the sametime, voltage generatedby the Hall
element (HA : H253) of the left reel carrier is
applied to pins 2 and 3 of IC903, with output
from pin 1.
5. The outputs noted in 3 and 4 above are applied
to pins 30 and 31 of IC904 (PD6008) where
they are processed to obtain data on the
amount of tape time remaining. This data is
output from pins 13 thru 19, and 26 thru 29.
6. During the few second interval that data pro-
cessingis taking place in step 5 above, there is
no data present in IC904, and this causes
the
output from pin 2O to vacillate between high
and low, switching Q921 ON and OFF causing
the dot indicator to blink. This reports initial
data acquisition.
7. During the time the dot indicator is blinking,
the numerical display will show preliminary
data, switching to an accurate display of the
calculation result a few seconds
later.
8. As the processed
data is stored in IC904, pin
20 will be locked high and Q921 will remain
ON keeping the dot indicator illuminated.
This reports the fact that the counter is indicat-
ing realtime.
9. Remaining tape time is continually processed
during tape travel to update the counter.
10. The unit indicated by the counter during the
PLAY mode is seconds.Inthe FAST mode,10
second
units areshown.
1l.If during tape travel, the STOP or PAUSE
mode is entered. the counter will hold the
valueat the point of entry.
l-2.When the tape reachesthe "00.00" point on
the counter, the "00.00" display will be held
for approximately 30 seconds to account for
slight differences in tape length (even though
the tapemay continue traveling).
o TAPE
CAPACITYswitch
The TAPE CAPACITY switch (S1018)isusedto
allow for various tape lengths to be processedfor
the tape time remaining display. Switching S1018
ON and OFF produces the logic levelsat pins 38
and 39 of IC904 (PD6008) shown in Fig. 1-30.
Fig.
1-30 Tapecapacityswitch
o Tapetraveldirectionindicator
LED indicators areprovided sothat the operator
can determine whether the tape is traveling in the
FWD or REV direction.
1. During the FWD mode of travel, the output
signal waveforms from pins 9 thru L2 otIC9O4
(PD6008) areasshownin Fig. 1-33.
2. These signalscycle through Q914 thru Q916,
turning them ON and OFF, thereby illuminat-
ing D1 thru D3 to indicate the forward direc-
tion of tape travel.
3. During the REV mode of travel, the output
signal waveforms from pins 9 thru L2 of
IC904 (PD6008) are as shown in Fig. 1-34.
4. These signalscycle through Q914 thru Q916,
turning them ON and OFF, thereby illuminat-
ing D4 thru DGto indicate the reversedirection
of tape travel.
5. The blinking rate of D1 thru D6 is determined
by the mode the mechanism is in, and this
information is receivedthrough pins 33 thru 37
of IC904.
19

+ FwDrNDrcaroR
€ REV
TNoTCATOR
REV
PLAY
REW
PAUSE
Fig.
1-31 Tapetravel
direction
indicator
P06008 (
IC904 )
PIN
9 OUTPUT
PINIO
OUTPUT
PINII OUTPUT
PIN
I2 OUTPUT
Fis.
1-33
P06008( rC904)
PIN
9 OUTPUT
PIN
IOOUTPUT
PINII OUTPUT
PIN
12OUTPUT
Fis.
1-34
ro-l
]_I----a
T
t-J
ru
OUTPUT
SIGNAL WAVEFORM
1
Outputsignal
waveform1
l*o'1
-l___J-----l
ru L-J
-L----J-
OUTPUT
SIGNAL
WAVEFORM
2
Outputsignal
waveform
2
Fig.
1-32 PD6008 input/output
table
a Memory
stop
When the MEMORY switch (51001) is placed
ON, the tape may be moved ahead or backed up
in the fast mode, automatically stopping when it
reaches
"0000" on the tape counter.
AIso, when the counter indicates real time, the
tape can be moved in the fast mode to the point
equivalent to "0000", where it is automatically
stopped.
1. When the tape is in the fast travelmode, alow
level output is produced from pin 25 of ICg04
(PD6008) when the tape counter reaches
"0000".
2. This output passes via the TIMER switch
(S1017), and S1001 to IC310 (PD6006),
whereit is appliedto pin 4.
3. The low input at pin 4 signals the program
written into IC310 to place the mechanismin
the STOPmode.
llowever, if one of the MS/SKIP, MUSIC
REPEAT, BLANK SEARCH oTINDEX SCAN
switches is activated, IC310 will not transmit
a STOP command even with a low input
present
at pin 4.
STOP
COMMANO
TO MECHANISM
WHEN
SrOrT
rN REC,METViORY
STOPDTSABLED
Fig.
1-35 Memorystop
4.
MECHANISM
MODE PD6OOB PIN No
INPUT PIN OUTPUTPIN
33 34 35 37 9tl t2
o
3
STO
PLHHHHHHH
LHL H H SEEFlG. 1-33A=6OmS
REW LH H H SEE
FlG. 1-34A=60mS
PLAY LLHHHiEE FlG. 1-33A=50Omt
FEL LLH H
PLAY PAUSE LHHL
H H H
REC PAUSE L H HL
PAU
SE LHHHL
r
G
STOP HH H H HHHH
n L H H SEE FlG. 1-33A=6OmS
REW HH H HSEEFlG. 1-34A=6OmS
PLAY HHHHiEE FlG. 1-34A=5OOmt
PLAY
PAUSE nLH H H H H
PA
USE H H H
20