Fast Forward Andrewind; Recording And Record Muting - Teac C-1 Service Manual

12
TAPE TRANSPORT SECTION
2-5 FAST FORWARD AND REWIND
Pin 20 of the SYS-CON goes high in the F. FWD mode
while pin 20 goes high in the REW mode.
Both operation signals are sent to the reel motor control
PCB and used to operate the reel motors. The signal is
also used for the following operations.
Route (1): Operates the brake solenoid and releases the
brake.
Route (2): Sets the end stops circuits which receives the
output signal of the tape end detection circuit
and resets the SYS-CON in the standby condi-
tion. Refer to pargraphs 2.7 and 2.8 for details
of this circuit.
Route (3): Sets the automatic rewind stop circuit in the
standby condition only in the REW mode.
Refer to the paragraph 2.8 for details of this
circuit.
Route (4): Turns on Q512 as well as charging C516.
With Q512 turned on, this circuit inhibits
outputs of pins 16 (REC), 17 (PLAY) and 18
(PAUSE). When the operation is switched from
F. FWD or REW mode directly to PLAY, REC/
v7 R532
RSS To Pause r ly 3
D513 D514
T-1299
1g TO.TAPE END
9—~—DET. CIRCUIT
R534 0528
PLAY, PAUSE or REC/PAUSE mode, this
circuit is used to delay the switching until the
tape has completly stopped. When the PLAY
button is depressed during the fast forward
operation, for example, pin 20 goes low imme-
diately while pin 17 goes low. However, since
Q512 is being turned on, the output signal of
the pin 17 is bypassed in route (5) even if pin
17 goes high, and the head, brake and pinch
solenoids are not actuated.
When pin 20 goes low, the signal in route (1)
stops, the brake solenoid is turned off, and the
reel table brake is applied and the tape is
stopped. The charge in C516 starts discharging
when pin 20 goes low. After C516 has dis-
charged, Q512 turns off and the PLAY signal is
no longer inhibited. The delay time due to
C516 is about 200 milliseconds.
REC SIGNAL TO AMP
0548 HEAO SOL. DRIVER a
0522 , 053!
PINCH SOL: DRIVER
0527 , 0533 |
0529, 0530, 0535
ay ee 7
BRAKE SOL, ORIVER |
0523 , 0532
0524, 0525,0534
END STOP CIRCUIT
Q520, 0521
AUTO REW. STOP CIRCUIT
0506 ~ 0508
Fig. 13 Fast Forward and Rewind Circuit
2-6 RECORDING AND RECORD MUTING
Recording and record muting are impossible when pin 5 of
the SYS-CON is high (when the erase protection tab of a
cassette is broken off and S694 is set to the DISABLE posi-
tion). When the RECORD button and the PLAY button
are depressed together with S694 set to the ENABLE posi-
tion, pins 16 and 17 go high and the REC PLAY mode is
selected.
If the RECORD button and the PAUSE button are de-
pressed together, pins 16 and 18 go high and the REC
PAUSE mode is selected. The tape motion is controlled by
the outputs of pins 17 and 18 as previously described.
When the pin 16 goes high, a REC signal is sent to the am-
plifier section and at the same time Q503 turns on and
lights the record indicator. The REC signal turns off the
muting circuit of the recording amplifier and operates the
bias oscillator. The output of the pin 16 turns on Q631 and
operates the relay K631. The relay K631 inhibits the pitch
control function during recording. (Refer to the Section 3)
The record muting mode is selected only when the REC
MUTE button is depressed during the REC PLAY opera-
tion. In this case, the record mode in not reset (pins 16 and
17 are still at the high level) and pin 15 goes high. The
REC MUTE signal of pin 15 turns on Q501 and lights the
REC MUTE indicator and mutes the recording amplifier
only. Since the bias oscillator is being operated with the
REC signal (output of pin 16), the tape runs without being
recorded and a black space is recorded on the tape, The
REC MUTE mode can be reset by the PLAY, PAUSE, F.
FWD, REW and STOP buttons.