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1. MECHANICAL DESCRIPTIONS
1.1 MechanismOperation When the mechanism, presently in the FWD-
The various mechanical sections of the recorder PLAY mode, is switched to the REV-PLAY mode,
are operated using the capstan motor to provide a direction operation is required, then the mecha-
the driving force. The various modes are activated nism will make the transition following the steps
by solenoid L and R, and these are controlled by listed below. (Refer to Fig. 1-2).
commands from CPU PD6006.
Both the capstan and reel-motor are direct-
drive motors fitted with a Hall sensing element.
Reel-motor L and reel-motor R (hereafter called
RM L, RM R) are used exclusively for tape take-up
in the FF, REW, PLAY, and REC/PLAY modes.
The direction of rotation and rotational speed of
these motoni are controlled by commands from
CPU PD6OO6.
The right side capstan motor is the DD type, and
the left side capstan motor is belt-driven by the
right side-motor. A sub-rotor acts as the actual
capstan. (Refer to Fig. 1-1).
The mechanism forming the right and left-hand
side of the unit is essentially symmetrical in
configuration, and in forward and reverse (here- Fig. 1-1 Mechanical
construction
after abbreviated FWD, REV) operations, each
side acts together. This description covers the
mechanical operations for FWD movement.
r Basic Operations of the Mechanism
The mechanism assumes three different states:
STOP, PAUSE,.and PLAY. Consequently, since it
can travel in the FWD and REV direction, there
are a total of six states possible. There is also a
direction operation for switching between FWD FWO
and REV travel. Transition between the FWD PLAY
and REV state will be described using only one
example. Fig. 1-2 mode transition(example)
Mechanism
Mechanism Mode Transition Flow State Mode
FWD REV
S T OP STOP STOP state sToP, (
D t R E C T | O ND l R )
FW0 ttu pAUsE P A U S E , P L A Y/ P A U S E ,
PAUSE
PAUSEstate R E C - P L A Y , P A U S E,
/
FF, REW.
FW0 REV
PLAY PLAY PLAY state PLAY, REC,/ LAY.
P
Fig. 1-3 Mechanism
mode transitionflow and modes
Direction switch ON REV-PLAY entered, thereby con-
1. Instantaneous transit from FWD-PLAY to cluding the switching operation.
FWD-STOP. The above operational flow is also shown using
2. Approx. 500msec after FWD-STOP entered, interconnecting arrows in Fig. 1-3. This figure
dirction operation effects REV- additionally shows other mechanism states possible
STOP. with the various modes.
3. Approx. 425msec after REV-STOP entered, Next, the mechanism operation when switch-
REV-PAUSE entered. ing between the various states (in the FWD direc-
4. Approx. 325msec after REV-PAUSE entered, tion) will be described.
Solenoid R A s s i s tg e a r R A s s i s tg e a r L Solenoid L Assist gear L Hook L Hook R Assist gear R
Trigger lever R Capstan motor Trigger lever L Sub-rotor Cam follower lever Switching plate Pinch-roller R
Fig. 1-4 construction(Rearview)
Mechanical
Fig. 1-5 Mechanical
construction(Front view)
1. MechanismTransition from STOP to PAUSE
Mechanism viewedfrom underneath
1. Upon command transmissionfrom PD6006, 3. Rotation of assist gear R is meshed with the
solenoid R turns ON (plunger retracted). capstan motor.
(Fie. 1-6).)
2. The movement of the solenoid plunger causes
the trigger lever R to disengagefrom the
stopper, allowing the assist gear R to turn.
Solenoid R
Assist gear R
Plunger
Trigger
lever R )
\
(@
\-r-__
\____---- --,
FiS.1-7 STOP-PAUSE
operation2
Capstan motor
\\_'l
,'/ -_\-/
Fig. 1-6 STOP-PAUSE
operation1
5
4. After assist gear R has tumed through about 2 . As the B point is raised, hook R (coupled to B
3/4ths of a revolution, it disengagesfrom the point) is also raised.
capstan motor. 3 . At point C, hook R catches the coupling plate
D . Since solenoid R is in an ON state, the stopper and continues to rise, carr5ring the coupling
on assist gear R contacts trigger lever R at plate and pinch-roller drive-plate with it.
point A, and stops. The above series of opera- 4. The pinch-roller drive-plate continues to rise
tions covers the events occurring on the back- until the pinch-roller goes into a PAUSE
side of the mechanism. Next, the operations status, then stops.
occurring simultaneous to the above, but as
viewed from the top of the unit will be given.
Cam follower ,"8
::":y \ Pinch-roller drive-plate
F i g . 1 - 1 0 S T O P - P A U So p e r a t i o n
E 5
Fig. 1-8 STOP-PAUSE
operation3
2. MechanismTransition from PAUSE to PLAY
Mechanism viewedfrom the top Mechanismviewed from underneath
1. As assistgear R rotates, its cam drives the B Solenoid R is presently ON, and the mechanism
point of the cam follower lever in an upward is in a PAUSE state.
direction. 1. Upon command transmission from PD6006,
solenoid L turns ON (plunger retracted).
2. The movement of the solenoid plunger causes
sorenoid the trigger lever L to disengage from the
"i- I
stopper, allowing assist gear L to start tuming.
: ^-l-. L,-.j
lii'qr-
' ij.1
i o() t5,'
''.,i&)lI,i
,ii)- -'
ngger
lever L
Fig. 1-9 STOP-PAUSE
operation4 /
----/ "!Y-"
F i g .1 - 1 1 P A U S E - P L A Y o p e r a t i1 n
o
3. Rotation of assist gear L is meshed with the Mechanismviewed from the top
sub-rotor. 1. As assist gear L rotates, its cam drives the E
point of the cam follower lever in an upward
direction.
2. As the E point is raised, hook L (coupled to
E point) is also raised.
::":-/
Fig. 1-12 PAUSE-PLAYoperation2
4. After assist gear L has tumed ttrrough about
3/4ths of a revolution, it disengagesfrom the
sub-rotor. Fig.1-14 PAUSE-PLAY
operation
4
o . Since solenoid L is in an ON state,the stopper
on assist gear L contacts trigger lever L at 3. When point E reaches the same height as point
point D, and stops. B, it stops. The head and pinch-roller at this
point is shown in Fig. 1-15. Here, since the E
point has reached the same height as the B
point, the X point rises higher than that of
the PAUSE status. Consequently, the head
makes contact with the tape, and the tape is
Dr pinched between pinch-roller R and the cap-
stan shaft, completing PLAY mode entry.
+\
i\
'-?\
\,1'\
Trigger
lever L
ol
\.*,]
Fig. 1-13 PAUSE-PLAYoperation3
Head
Fig. 1-15 PAUSE-PLAYoperation5
3 . Solenoid L then goes OFF, returning trigger
lever L to it's original position.
4. Rotation of assist gear L is meshed with the
sub-rotor.
Fig. 1-16 PAUSE-PLAYoperation6
3. DirectionOperation
Mechanism viewedfrom underneath
Mechanismis presently in STOPstatus
1. Upon command transmission from PD6006,
solenoid L turns ON (plunger retracted). Fig.1-18 DIRECTION
operation
2
2. The movement of the solenoid plunger causes
the trigger lever L to disengage from the o. After assist gear L has tumed through about
stopper, allowing assistgear L to start tuming. 3/4ths of a revolution, it disengagesfrom the
sub-rotor.
6 . When the sub-rotor and assist gear L become
Solenoid L
unmeshed, since the solenoid lever has already
retumed to its out position, spring tension is
allowed to return the assist gear to its original
position after making only one revolution.
This completes the operation.
'Trigger
,leverL
Stopper
\
I
I
'----t'
'Trigger
llever L
Fig.1-17 DIRECTION peration
o 1
@
I
\
l
Sub-rotor
----/
3
F i g .1 - 1 9 D I R E C T I O N p e r a t i o n
o
o
Mechanismviewed from the top 5 . As the slide plate moves from right to left,
1. As assist gear L rotates, its cam drives the G the head rotates to the REV direction attitude.
point of the cam follower lever in an upward (Refer to Fig. 1-23)
direction. 6. After assist gear L has turned through about
2. As the E point is driven upwards, point F on 3/4ths of a revolution, it disengagesfrom the
the right-hand side of the cam follower lever sub-rotor. Spring pressure forces it back to its
starts forcing the switching plate to the left. original state, completing the direction opera-
3. As the switching plate is forced to the left, tion, and switching the unit from REV to
it canies the G point on the coupling plate to STOP.
the left with it.
Fig.1-22 DIRECTION peration
o 5
4. Head Roation
Fig.1-20 DIRECT'ION
operation
4 As the slide plate moves from right to left in the
direction operation (described above), the pin on
4. Since the H point on the coupling plate func- the sector gear also is forced from right to left.
tions as a support point, as the G point is This is shown in Fig. 1-23. As the sector gear pin
shifted to the left, the slide plate also moves to goes past the center point, the force of the gear
the left with the two plates above. This is spring rotates the sector gear through approxi-
shown in Fig. 1-21. mately a 90' angle. This causes the head meshed
to sector gear to rotate 180", placing the unit in
a REV state.
Slideolate
frr
-
Slide plate Fig. 1-23 Head rotation operation 1
F i g .1 - 2 1 D I R E C T I O N p e r a t i o n
o 5
2. CIRCUIT DESCRIPTIONS
2.1 PLAYBACK FLOW then starts transmitting control signals from its
This signal picked up by the playback head is various output pins in accordance with which key
amplified by the two-stage, direct-coupled ampli- was activated. (Refer to Fig. 2-3.)
fiers, Q501 and Q503. If the NORM position (Ee) The following sections will describe the various
is selected, the NF circuit between the collector circuit operations occurring when a mode key is
of Q503 and the emitter of Q501 will set equali- activated. Operations will be described for the
zation bias to 120ps. Changing the selector posi- FWD direction of travel. (Except where other-
tion to METAL or CrO2 turns Q505 ON, and Ee is wise specified, the pin nos. will be for PMB001.)
switched from 120ps to 70ps, thus correcting
frequency response for these tape formulations. 1. STOP Mode Key ON
The output level from the EQ AMP is adjusted Mechanism
by a potentiometer and further amplified by the The 16-bit serial data transmission from pD6006
flat amp, Q507. Output from the flat amp is will cause pin 7 and 8 of PM3001 to go high,
applied to pin 15 of the Dolby IC. turning SOL L and R OFF. The mechanism will
The Dolby circuit consists of IC601 (HA11226), thus be placed in a STOP status.
and its output is taken from pin 8 of IC601.
It then passesthrough the Dolby amp (ICB02) and Motor
is applied to LINE OUTPUT. Pin 4 and 5 will be low, and the reel motor will
be in a STOP status.
2.2 RECORDINGFLOW Signal path,andothercircuits
Signals input to the MIC jack are amplified by When pin 6 goes low, the reed relay Ryb01 is
the mic amp, Q801, then passedthrough the MIC/ activated. Consequently, point A of the REC/
LINE selector switch and into the INPUT volume PLAY head is at gxound potential, and the head is
where the signal is adjusted to the proper level. in the playback mode.
This adjusted-level signal is then applied to flat Pin 10 and 11 go high, turning Q3OG,e802, and
amp Q803.
Q304 ON. This grounds the input of the REC
After amplification by the flat amp, the signal AMP. LINE OUTPUT is also grounded, so no
passesthrough the MPX filter and is input at pin
sound is output.
2 of the Dolby IC. Output is taken from pin g.
Pin 12 and 13 go low, tuming Q310 and ebl3
The level of the output from the Dolby IC is
OFF. This causes the oscillation of the OSC
adjusted by potentiometer, and passedthrough the
circuit to stop. Also, since Q513 is OFF, signals
REC AMP (IC501) where the signal is corrected
picked up by the REC/PLAY head are input to the
for best compatibility with the tape being used.
PB AMP.
It is then fed to the recording head for use as the
recording signal. 2. PLAY Mode Key ON
Mechanism
2.3 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. 2-19).
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 PMB001 as Motor
16-bit serial data, and PM3001 then uses this data Pin 4 goes to a low level, while pin b 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 tuming.
data transmission is output from pin b of PD6006.
This is shown in Fig. 2-1. Also a clock pulse is PD6006
output from pin 7. (Data and clock pulse trans-
mission occurs once each time the key is activated.)
The 16-bit serial data is applied to pin B of the
expansion IC, PM3001, and the leading edge of 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 pMg001
a
SignalPath 3. FF ModeKey ON Motor
As pin 10 goes low, the Dolby amp muting Mechanism Pir
transistor (Q302) and line muting transistor Pin 7 goes high and pin 8 goes low. This tums Lin
(Q304) are turned OFF. Thus, the signal is present SOL L OFF and SOL R ON, placing the mecha- Signa
at LINE OUTPUT. nism in a PAUSE status. Sa
M S C I R C UT
I
_-4)- PULL.UP RESISTOR PA3010
HALF SW Xtql
Ms EE-ser
PM3OO1 EXPANSION )
( IC
REAoER fr:56p
SENSING DATA
IF: INTERFACE
M. REPEAT SR: SHIFT
RGISTER
T/ BlS CLOCK
t.i:@T--r---T--t
lPilib\ lREc
IPL^YloFFl
T- PLAY
l- 35 T;TL
#
T;l
| 34 lLlH lHl AUTORESET
T- REC STB crRcurT
ffif-rl-']-l
| 33 lxlL lHl
MOOET SKIP
|-.----------l.------|---------H
32 lLlH M O O E Mll
I lHl
F-R SW B/S CT.7R ONLY
FWD S I G NAL PATH
REV
rjrEc MUTE
REc sENsoR AUTO BLE
l--
REC irUT PAUSE INO
REC,/PB
CT-7R ONLY REC MUTE HEAD
REC
i-;'aF;-l
IND
4PLAY
FLA7 Ms MurE
CT.7R ONLY
r--{,----'l
PAUSE M/R INO
I FF
FF I./S IND
l_REW
REW B/S IND
!sToP
STOP SKIP INO
. otR
OIRECTION GND
Q3lO
Fig.2-2 Control systemblock diagram
Motor 4. REWModeKey ON
Pin 4 goes low and pin 5 goes high, placing RM Mechanism
L in a STOP status and eausing RM R to tum.
Pin 7 goes high and pin 8 goes low. This turns
Pathandothercircuits
Signal SOL L OFF and SOL R ON, Placing the mecha-
Same as in the STOP status. nism in a PAUSE status.
Motor
Pin 4 goes high and pin 5 goes low. This tums
RM L on and places RM R in a STOP status.
Pathandothercircuits
Signal
Same as in the STOP status.
icrRcurT iroroErl8ggll
IREE!
5. REC/PLAY Mode Key ON
Mechanism
Same as PLAY Mode Key ON.
Motor
Same as PLAY Mode Key ON.
SignalPathandothercircuits
CAPSTANMOTORCIRCUIT
When pin 6 goes high, the reed relay RY501 is
3 0 0 1 ( E X P A N S T OIN )
C
turned OFF. ConsequenUy, bias is applied to the
TT
REC/PLAY head by the output from the REC
AMP and the OSC circuit.
As pin 10 and 11 go low, the Dolby amp
muting transistor (Q302) and LINE MUTE tran-
P42007 PA2012 sistor (Q304) are turned OFF and sound is output.
Also, since Q306 is OFF, the input signal is applied
to the REC AMP.
rol When pin 12 and 13 go high, Q310 and Q513
are tumed ON, and the BIAS oscillator circuit is
soL
trnE
R allowed to supply bias to the head. Turning Q513
ON also enables the head to go into a record-
only status.
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.
Signal Pathandothercircuits
Same as STOP status. (The PAUSE LED is
illuminated however.)
7. PAUSE Mode Key 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 a PAUSE status.
Motor
FOi Tmf rux lto Same as STOP status.
Path
Signal
Same as STOP status. (PAUSE LED is illumi
nated however.)
10
8. REC/PLAYPAUSEModeKey ON Pin 12 is at a low level, and Q310 turned OFF,
Mechanism stopping the OSC circuit.
Pin 7 goes high, and pin 8 goes low. This turns Pin 13 goes high turning Q513 ON, thereby
SOL L OFF and SOL R ON, placing the mecha- allowing the head to function in the record-only
nism in a PAUSE status. mode.
Pin 14 of PD6006 goes low, causingthe PAUSE
Motor
LED to illuminate.
Same as STOP status.
9. Direction Key ON (in STOP status)
SignalPathandothercircuits
Mechanism
As pin 6 goes high it turns reed relay RY501
Pin 7 goes low for a 275msec interval, and pin 8
OFF. goes high. This causes SOL L to turn on for only
This, bias is applied to the REC/PLAY head by
275msec, and since SOL R is OFF, the mechanism
the output of the REC AMP and the OSC circuit.
goes through a direction operation from FWD-
When pin 10 goes low, Q304 and Q302 go OFF
STOP to REV-STOP.
and a signal is present at LINE OUTPUT.
Since pin 11 is high, Q306 is ON, and the input Motor
to the REC AMP is muted. Same as STOP status.
Pin 12 is at a low level, and Q310 tumed OFF, Signal
Pathandothercircuits
stopping the OSC circuit.
Same as STOP status.
PM30O1 O U T P U TS T A T E B Y M O D E
Pin STOP PLAY REC/PLAY STO P PLAY REC /PLAY
REW PAUSE PAUSE PAUSE
No.
FUNCTION\ F w D I R E V FWD R E V F W D R E V F W D R E V F\ry0 R E V F w D I R E V FWD I REV F W OI R E V
RM. L L H L t\4 L M L
,or' L
5 RM. R L H L M L tvt L
toa' L L
HEAD SW '( L L L n L L H
rrrooE
7 SOL. L H H IL HIL L
{OFF)
L H H]L H]L
8 SOL. R H LH LH L L
(OFF) FI LIH LIH
PB. MUT n d H L L H H
{oN) H
to LINEMUTE H H H L L n L
(oN) fl
tl REC MUTE n FI H H L fl H
( o N) H
t2 BIAS L L L n
(O F F ) L L L
t3 REC L L L L H
(orF) L L H
t4 REW IND L H L L L
IOFF)
tc rr IND L torar H L L L L L L
PLAY IND L L L H H L L
,or'
PD oo5
t4 PAUSEINO
H
(OFF)
n H H n L L L
Fig. 2-3 PM3001Output stateby mode
Applicable
Pin
Symbol
r/o Description Model
No. itatus
CT.7R CT-6R
1 Extal Used by internal quartz oscillator a\
Pin2 - GND
2 Xtal External circuit terminal f = 3.58MHz
3 RESET IN CPU reset input (effective low, normally high)
4 M.STOP IN Memory STOP input (effective low) o X
5 DATA OUT DATA output to PM3001 onrn !___gJ-il__g- - - ----t-[, L9__ o
6 NC
7 CLOCK OUT CLOCK output to PM3001 ,fl[-l ,f
..o.^l ,f-l
Serial
output to o
PM3001
8 NC
9 STB OUT STB output to PM3O01 STB
10 SKIP OUT SKIP key scanoutput _r----1_, _r----L KEY
o o
-l_J-
11 M/l OUT MUSICREPEAT.INDEX SCANkey scanoutput ]J-
---1_r ---l_f
SCAN o o
output
12 B/S OUT BLANK SEARCHkey scanoutput x
13 AUTOBLE OUT AUTO BLE start output [ **"*;*----ll l-* r-z.s X x
14 PAUSE ND
I OUT PAUSE indicator output (effective lowl o
I ndicator
R E CM U T E output
15
IND OUT REC MUTE indicator output (effective low)
MS MUTE output, PA301O signal
MS MUTE output (low levelwhile reelmotor turning
16 M SM U T E OUT during blank detectoroperation
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 ) X
18 r / st N D OUT INDEX SCAN indicator output (effective lowl I ndicator X X
19 B/S IND OUT BLANK SEARCH indicator output (effectivelowl output
X X
20 SKIP IND OUT SKIP indicator output (effective low) \J
21 GND GND o
22 DIRECTION I N DIR (directionl key input o
23 STOP IN STOPkey input
24 REW IN REWkey input Mode
25 FF IN FF key input Key
input
o
26 PAUSE IN Pause
key input
27 PLAY IN PLAY key input
28 REC IN REC/PLAY key input o
29 R E CM U T IN REC MUTE key input
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 dl o w , d i s a b l e d h i g h ) Mechanism
31 F-R SW IN switchinput (FWD: L; REV: H)
FWD/REVsensor SW input
32 M O D EI IN Mode
Mode selector switeh input selector
33 MODEII IN SW input
34 T.REC IN Timer RECswitchinput Timer
mode SW
o
35 T-PLAY IN Timer PLAY switchinput input o
36 r/B/s IN INDEX SCAN, BLANK SEARCH, SKIP key input Key
matrix
o
37 M.REPEAT IN M U S I CR E P E A T e y i n p u t
k input X
38 SENSING IN pulseinput (from PA2010pin)
Sensing __j-LJ-LI-L: Reelturnins o
39 LEADER IN Tape leaderpulsedetectorinput (from pin 2, PA301O) n *Tape leaderdetected X
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 \J
selection; H level all other times)
41 HALF SW IN loadingswitch input (Loaded:L ; Unloaded:H)
Cassette o
42 VDD *5V power source
FiS.2-4 PD6006Pin description
te
PA3010
2.4 TAPE LEADER DETECTORCIRCUIT
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 of travel, 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. 2-6 detectorcircuit
Tapeleader
ing a difference in the amount of light passed by
PIN
the coated portion of tape, and the amount passed NO,
t6
by the transparent leader.
The output from pin 16 of PA3010 is converted
to light by the LED, and passesthrough the path
shown in Fig. 2-5 to be picked up by the photo- A
transistor. During tape travel, the amount of light
received by the phototransistor is quite small, so rr+
the input level at pin 7 is held low. This causes 5
";,[TL-----r-
the charge and voltage at pin 3 and 4 to also be :::l]l:ll-----]
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
passes into the light path, the amount of light
n
picked up by the phototransistor suddenly in- I
creasesthe input to pin 7. This causespin 3 to snap COATED TAPE LEADER TAPE
high, consequently applying a high input to the +
terminal of the comparator. Output from pin 2 Fig.2-7 detectorwaves
Tape leader
then goes high. As pin 3 goes high, the capacitor
connected to pin 4 starts charging, raising the 2.5 END SENSOR IRCUIT
C
input level to the - terminal of the comparator. O CTR
When the level of the - terminal reaches that of When the reel motor starts turning, a sensing
the + terminal, the output from the comparator pulse is transmitted from pin 13 of IC PA2010
snaps from high to low, and the output pulse (used to control the reel motor) to pin 38 of
taken from pin 2 appears as shown in Fig. 2-7. PD6006. (This pulse is taken from the Hall element
CPU PD 6006 uses this output pulse to control and shaped into a square wave by PA2010.)
the various mechanisms performing the mecha- When this pulse is maintained at either a low (L) or
nical functions of auto-reverse and automatic high (H) level for a period exceeding three seconds,
stop. PD6006 interprets that to mean the end of the
tape and thus switches to the next mode of opera-
tion.
LED REFERENCE PIN
If the mechanism is in the fast-forward (FF),
_
5l
J -lt F - >--)-+
--f
rewind (REW), or record-playback (REC/PLAY)
E
--r-
IAtsE
mode, the next mode entered is STOP. If it is
#P! e*ot.".oo presently in the PLAY mode and the ? reverse
lA- | w t T Hw t N O O w
LIT---I mode switch is selected, it also enters the STOP
PHOTOTRANSISTOR
mode. But if pQ is selected, it first goes through
a direction operation, then into a PLAY status.
Fig. 2-5 Tape leader
detectorsection
O CT.7R
Since CT-7R is equipped with a tape leader
detector circuit, it goes into a STOP status or goes
through a direction operation before reaching the
point where the end sensor circuit is activated, so
normally the end sensor circuit will not operate.
However, where there is no leader on the cassette Consequently, when an input signal is present,
tape, or where there is an insufficient difference pin 13 is at a low level, and no signal produces a
in the infrared transmission factor between the high output. This output is used by each of the
coated portion and leader portion of the tape, or function operations (MS/SKIP, INDEX SCAN,
in case the reel motor stops rotating before the BLANK SEARCH, MUSIC REPEAT).
tape leader is detected, the end sensor circuit is
then activated, placing the unit in the STOP mode. PMSMUIE. L (PIN II) ( B L A N K S E A R C H O P E R A T I O N) PMS MUTE -. H (PIN I
However, in the REC/PLAY or PLAY mode, a
direction operation may be called for depending on ,,1,Ll
'l'"1"
i.l,/,.. ,ii r./fir/,.,, ,t.
r'
1-" rrr?"
the position of the reverse mode switch.
ffi ffitffi ilffimm
-TLJ-L
a
MM W
5V
--:::::-.- Toms--tl
_ i-- 2a=- t---
t2 4VT
r\/
f /
\\ ,/ /
RIGHT EEL
R
MOTORHALL
PA20rO PD6006
E L EM E N T 3 It t l f-i
Fig. 2-8 diagram
End sensor
2.6 BLANK DETECTOR IC PA3OlO OPERATION Fig. 2-10 Blankdetectorwaves
When the function key is placed ON, and the
reel motor starts turning, pin 16 of PD6006 2.7 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- 2-11. 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
accompanying table. the pulse train, and starts operation of the selected
This output is used to turn Tr1 ON, and this in mode accordingly. (CT-6R does not have BLANK
tum allows capacitor C connected to pin L2 to SEARCH or MUSIC SEARCH capability.)
dump its charge through Tt1. Thus, pin 13 goes to
MUSIC REPEAT KEY ON
a low level.
When there is no input signal present, Tr1 turns
OFF, capacitor C starts recharging, and approxi-
mately ?Omsec later, a high level is output from
pin 13.
PA3010
a: 57rS a. 6O)s . c = 27 ns
+a
Fis.2-11