Onkyo TA 2047 Service Manual

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TA-2047

SERIAL No. 3196

ONKYOc SERVICE MANUAL

STEREO CASSETTE
TAPE DECK
MODEL TA-2047

Black and silver inodels
UDN, UDC, UD 120V AC, 60HZ
UG 220V AC, SOHZ
UW 120 or 220V AC, 50/60HZ
UQA, UQB Z4OV AC, SOHZ

SAFTY-RELATED COMPONETN WARNINGII

COMPONENTS IDENTIFIED BY MARK A ON
THE SCHEMATIC DIAGRAM AND IN THE PARTS
LIST ARE CRITICAL FOR RISK OF FIRE AND
ELECTRIC SHOCK REPLACE THESE COM-
PONENTS WITH ONKYO PARTS WHOSE PARTS
NUMBERS APPEAR AS SHOWN IN THIS MANUAL.

MAKE LEAKAGE-CURRENT OR RESISTANCE
MEASUREMENTS TO DETERMINE THAT EX-
POSED PARTS ARE ACCEPTABLY INSULATED
FROM THE SUPPLY CIRCUIT BEFORE RETURN-
ING THE APPLIANCE TO THE CUSTOMER

ONKYO®
AIIIIIII IIIIMPIIIIIIIIS

SPECIFICATIONS

Track Format:
Erasing System:
Tape Speed:

Wow & Flutter:
Frequency Response:

Signal-Io-Noise Ratio:

Input Jacks:

4 tracks, 2 channels
AC erase
4.8 cm/sec. (1-7/8 i.p.s.)
0.045% (WRMS)
20-16,000 Hz (30-15,000 Hz i3dB)
(normal position tape)
20-17,000 Hz (30~16,000 I-lz t3dB)
(high position tape)
2018,000 Hz (BO-17,000 Hz :3dB)
60dB (metal position tape, Dolby
NR out)
A noise reduction of 10dB above
SKHz and, (MB at lkHz is possible
with Dolby B NR, A noise reduction
of 30dB at SkHz is possible with
Dolby C NR.
Mjg jacks: 2
Input sensitivity: 0.3mV/600
ohm
Input impedance: 2.7 kohms
Line IN: 2
Input sensitivity: 60mV
Input impedance: 50 kohms

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TA-2047

Outputs; Line OUT: 2
Std output level: SOOmV (OdB)
Optimum load impedance; over
50 kohms
Headphone Jack: 1
Optimum load impedance18-200
ohm
Motors; DC servo motor: 1
DC motor: 2
Heads: Rec/pl: head: Special Hard Permalloy
Erase head: Ferrite
Power Supply: AC120V/60Hz
Power Consumption: 33 watts
Dimensions: 43 5(W) x 112(H) x 371(D)mm
(17-1/8 x 4-3/8x14»5/8")
Weight: 6.0 kg, (13.2 lbs.)

Specifications and external appearnee are subject to change
without notice because of product improvements.

SERVICE PROCEDURES

1. lnstulation resistance meaurement

Connect the insulatingresistance tester between the plug of
power supply cord and chassis.

Specifications; 500V more than 10 M9

2. Replacing the lamps
This unit used the lamps listed below.

Circuti No. Part No, Description
PLlOl 210090 150mA, 14V. Lamp
PL701 210183 0.06A, 14V. Lamp

CAUTION: Before replacing the lamps, be sure to unplug
the power supply cable.

FEATURES .

ACCUBIAS For the Best Performance With Any Tape

The ACCUBIAS system fine tunes the recording bias to
obtain optimum performance with any kind of tape (not
necessary with metal tapes). By setting precisely the correct
bias level, ACCUBIAS guarantees the tlattest frequency
response and highest signal-to-noise ratio possible with each
tape.

Dual Sensor Real Time Tape Counter

The tape counter circuit measures the speed of both tape
reels and compares them by microcomputer to provide
precise readings of remaining time. This dual sensor tech-
nique eliminates small errors in time calculations caused by
slight variations in tape thickness between different manu-
facturers to give the most accurate time indications
possible.

2-Motor Tape Transport with Separate Head Assembly
Motor

The tape transport system, along with the heads, is the
most important factor affecting the basic performance of
a cassette deck. To assure extremely stable and accurate

,2,

transport, this unit uses a DC servo-controlled capstan
motor. This motor is unaffected by fluctuations in the
power supply voltage and frequency and instantaneous
changes in load. A highly reliable simple drive transmission
system and precision vertical cassette holder further
enhance overall accuracy and stability. As a result, wow and
flutter is under 0.045% In addition, separate DC motors
drive the reel tables and head base and the head assembly is
constructed to move silently with no annoying clicks.

Dolby B and C Noise Reduction

Along with standard Dolby B NR, this unit also has the
even more effective Dolby C NR system. Dolby C NR
reduces tape background noi8se by ZOdB at SkHz, about
3 times more than Dolby B NR1 In addition to its wide
band noise recuction, Dolby C NR uses a sliding band
technique that varies the band width of noise reduction
according to the input level, thereby avoiding noise
pumping. Dolby C NR also has an anti-saturation effect
to reduce the chance of tape saturation in the high range.
All these features combine to eliminate the adverse effects
on tape sound that other noise reduction systems can cause.

Remote Control Unit Connector

With an optional remote control unit (such as the ROST),
this unit can be controlled evern while you are relaxing
in your favorite chair. All transport modes are included:
record, play, fast forward, rewind, stop and pause.

Sensitive 2-Color 10-Segment LED Peak Level Meter

The left and right peak level meters react instantaneously
to signals and the two-color layout assures that you wont
miss any potentially harmful input signals when setting the
recording level.

Auto Space Rec Mute Button
This button lets you insert unrecorded sections five seconds
long with just one quick tap.

Auto Music Control System (A.M.C.S.)

The AMCS automatically locates the beginning of every
song on a cassette in either the forward or the reverse
direction. When AMCS >> is pressed during the play mode,
tape is rapidly wound to the beginning of the next song and
the first 10 seconds (approximately) is played. Then the
tape is rapidly wound forward to the beginning of the next
song and about 10 seconds is played, This process continues
until the PLAY button is pressed to cancel AMCS operation
and return to normal playback. When AMCS >> is pressed
during the play mode, this process is performed in the
reverse direction.

Repeat Playback Modes

With this deck, you have a choice of two ways to play
a tape repeatedly: (1) Single repeat for one song; (2) Full
repeat for an entire cassette side.

Fully Automatic Tape Selection
This deck senses the type of cassette inserted and auto
matically sets the correct amount of bias and equalization,

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CHASSIS-EXPLODED VIEW

TA-2047