Onkyo TA 1900 Service Manual

Page 1

SERIAL NO. 3089

ONKYO® SERVICE MANUAL

STEREO CASSETTE
TAPE DECK
Model TA-l9OO

TABLE OF CONTENTS
Item Page

Specifications 2
Features 2
Service procedures 3
Mechanism operation 3
Alignment procedures 4
Exploded View 6
Mechanism-exploded view 7

PC board view (G/W model) 9
PC board-parts list (6/ W model) 10
Schematic diagram (G/W model) 11
PC board View (D model) 13
PC board-parts list (D model) 14
Schematic diagram (D model) 15
Component location 17
Packing procedures 18

ONKYOQ
Alllllll 60"lele

Page 2

TA-l

SPECIFICATIONS
Track System : 4-track, 2-channel stereo
Recording Syetem : AC bias
Erasing System : AC erase
Tape Speed : 4.8 cm/sec.
Wow and Flutter : 0.07% (WRM S)

30 - 14,000 Hz (30 ~
13,000 HZ inB) (normal
position tape)
30 7 15,000 Hz (30 -
14,000 Hz i3dB) (high position
tape)
30 - 15,000 Hz (30 7
14,000 Hz i3dB) (metal
position tape)
56 dB (metal position tape,
Dolby NR out)
A noise reduction of 10 dB
above 5 kHz and 5 dB at 1 kHz
is possible with the Dolby NR in
Microphone Jacks : 2
Minimum input level :
0.3 mV/6009
Input impedance :
5 k0
Optimum mic impedance :
60052 - 50 k9
Line In : 2
Minimum input level :
50 mV
Input impedance :
50 k9
DIN lack : 1(Only Q, W/G model)
Minimum input level :
0.1mV/ lkfl
Input impedance :
1 k9.

Frequency Response :

Signal-to-Noise Ratio :

Input Jacks :

FEATU RES

Hard Permalloy Head for Metal Tapes

To bring out the full potential of metal tape formulations,
the TA-l900 employs a new hard permalloy having superior
magnetic properties for the rec/pb head. The result is a
wide dynamic range, extended high range frequency
response and excellent resistance to abrasion.

Direct Loading System

The convenient direct loading system facilitatessure and
quick loading and unloading of cassettes. And because
everything is up front, the inner parts are readily accessible
for cleaning and demagnetizing.

Dolby Noise Reduction System

When turned on during recording and playback, this system
reduces tape hiss and raises S/N ratio by up to 10 dB
above 5 kHz.

Line Out : 2
Output level :
350 mV (at 0 VU)
Optimum load impedance ;
more than 50 kfl
DIN Jack :1 (Only Q, W/G model)
Standard output level :
350 mV (OVU)
Optimum load impedance :
more than 50 k9
Headphone Jack : 1
Optimum impedance :
89/2009
DC servo motor : 1
hard permalloy head and
three-gap ferrite erase head
TR216Diodes2111C22
LED : 6 (Only Q, W/G model)
TR : 14 Diodes : 11 IC :2
LED : 6 (Only D model)
120V/60Hz, 220V/50Hz,
120/220V, 50/60Hz or
240V/50Hz
12W

Outputs :

Motor :
Heads :

Semiconductors :

Power supply :

Power Consumption :

Dimensions : 418(W) x 120(H) x 290(D) mm
16-1/2 x 4-3/ x11-7/16

Weight : 4.8 kg (10,6 lbs).

Accessories : Pin-type connecting cords : 2

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

Full Auto-Stop Mechanism
Full automatic stop at the end of the tape safeguards
both tapes and tape transport from undue strain.

You are now the owner of a very high quality stereo
cassette tape deck. To ensure many long years of listening
enjoyment free of trouble, read this manual carefully and
familiarize yourself with all facets of operation. Failure to
do so may result in loss of performance and also in possible
malfunction.

Page 4

SERVICE PROCEDURES

Head Cleaning

Sound quality is greatly influenced by accumulation of
magnetic particles on the recording/ playback head.

For the clearest possible sound, be sure to clean the
head periodically, normally 2 - 3 times a month.

A dirty head will cause:

0 Poor sound quality (loss of high sounds)

O Decreased volume

0 Skipping

0 Poor erasing (incomplete erasure of previous recording)
To prevent these problems, clean the head and capstan
shaft with a cleaning pen or a cotton swab dipped in a
little alcohol.

Recording and Playback head Capstan

/

/

Erasmg head
Pinch Roller

A
Pinch Roller Cleaning

If the pinch roller is dirty, the tape may become tangled
and damaged by wrapping around the roller. Clean the
pinch roller when cleaning the head. Use a special cleaner

and cotton swab. Head cleaning materials must never be
used for the pinch roller.

MECHANISM OPERATION

Clutch ass'y

Supply reel

Roller

,3,

Demagnetizing

Residual magnetism builds up in the head after the
cassette deck had been used for a long period. This build-up
introduces noise and static into recording tapes and lowers
the high frequency range. To prevent this, demagnetize the
erasing and recording/ playback heads as other affected
metal parts (like the capstan shaft) once every 50 hours of
use. Keep the tape deck power OFF while using the
demagnetizer. Also place recording tapes far away from the
work area.

TAPE SELECTOR GUIDE

TAPE
SELECTOR EQ/BIAS EQ/BIAS EQ/BIAS
NORMAL HIGH METAL
BRAND (120 us) (70 us) (70 us)
*MAXELL XL-I XL-II MX
AGFA SUPER HIGH CHROM
DYNAMIC
AMPEX GRAND GRAND
MASTER 1 MASTER II
BASF Professional I Professional II Metal IV
Studio I Studio II
FUJI FL FX-II
FX-l
MAXELL LN CR
UD _
MEMOREX MEMOREX MEMOREX
(120 [1) (70 L0
RKO BROADCAST-I
SCOTCH MASTER I MASTER II METAFINE
SONY LN SHF CR
HFX LNX EHF (CD41) METALLIC
TKD AD D SA MA
ED 0D SA-X MA-R

Clutch ass'y

Motor pulley

Take»up reel