Pioneer ct 2070 r service manual

Page 1

CIRCUIT & MECHANISM

DESCRIPTIONS ORDER NO.
' ARP1 031-0

STEREO CASSETTE TAPE DECK

T-EO7ORIBKJ

0 This service manual is applicable to the KU type.
0 As to the repair and adjustments, piease refer to the CT-2070R [BK] service manual (ARP1032).

CONTENTS

1. DESCRIPTION OF TAPE TRANSPORT

OPERATIONS ....................... 2
2. CIRCUIT DESCRIPTIONS ............... 8
3. TIMING CHART ..................... 19
4. IC DESCRIPTION .................... 25

PIONEER ELECTRONIC CORPORATION 41. Megupo I/Chome. Meguro-km Tokyo 153, Japan
PIONEER ELEc'rnoNIcs senvtcE INC. Po. Box 17513, Long Beach, Cemfoma 9080! LISA. u».
TEL. [213] 4205700
PIONEER ELECTRONIC: [EunuaE] N.V. Kaecberglaan 1. 2740 Eeveren. Beiglum TEL: 0317752805
PIONEEH ELECTRONICS AUSTRALIA PTY. LTD. 1794 8:] Boundary Road. Eraeside, Victorie 3195, Austraha
TEL; [03) 58078911

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wCT--2C37CJFICBKJ

1. DESCRIPTION OF TAPE TRANSPORT OPERATIONS

The tape transport mechanism in this tape deck
consists of a capstan motor for driving the capstan,
a reel motor for driving the reel bases, and a
plunger solenoid for setting the various tape trans-
port modes. The basic structure of the tape trans-
port mechanism is divided into the following three
major sections.

1.1 CAPSTAN DRIVE SYSTEM

The capstan drive system consists of a capstan
motor used to drive the FWD (forward) and REV
(reverse) capstans by a belt looped around the
respective flywheels as shown in Fig. 1-1.

Capstan motor

R E V capstan

Flywheel

Fig. 1-1

FIR gear arm

Reel motor shaft

Gear (d)

(reel drive gear) \/\-\

Capstan belt

Capstan drive

1.2 REEL DRIVE SYSTEM

The reel drive system consists of gear (a) on the
reel motor shaft, F [R gear (b) engaged with gear (a)
but which can be freely moved to either side, and
reel drive gears (d) and (e) which are coupled to
gear (b) by the turning effect generated in the
rotational direction to thereby drive the take-up
reel. (see Fig. 1-2.)

The rotational direction of the motor is reversed
by changing the voltage applied to the motor, and
the tape transport speed changes (take-up torque
changes in playback, fast forward, and other modes)
are achieved by changing the level of the applied
voltage.

FWD capstan

Flywheel

\\ / Reel motor
\
$ \\ Gear (s)
' f§ F/R gear (bl
l

b
/ 5772/ Gear (e)
\ // (reel drive gear)

@ ~_\_//

C-R slide plate

Fig. 1-2 Reel drive