Sony tc rx 470 service manual

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TC-RX470

SERVICE MANUAL

US Model

Canadian Model

Dolby noise reduction and HX Pro headroom extension manufactured
under license from Dolby Laboratories Licensing Corporation HX Pro
originated by Bang & Olulsen.

DOLBY, the double-D symbol DE] and HX PRO are trademarks or
Dolby Laboratories Licensing Corporation.

SPECIFICATIONS

Recording system
Fastvwinding time

Bias
Heads

Motors

4-track 2-channel stereo

Approx 90 sec. (with Sony 060
cassette)

AC bias

Erasing head x 1 (ferrite head)
Playback/Recording head x 1

(SD head)

Capstan motor x 1 (DC servo motor)
Reel motor x 1 (DC motor)

ASiST (mechanical drive) motor x 1
(DC motor)

Signal-to~noise ratio (NAB, at peak level)

Model Name Using Similar Mechanism

TC-WR87O

Tape Transport Mechanism Type

TCM 200 R7

Inputs

Line inputs
(phono jacks)

Sensitivity

77.5 mV

input impedance

47 k ohms

Microphone inputs
(phone jacks)

Sensitivity (For a
low-impedance
microphone)

025 mV

Outputs

Line outputs

Rated output

032 V at a load

Dolby NR switch OFF B-Type C-Type
Cassette ON ON
Type lV (Sony METAL-8LT) 58 dB 66 dB 73 dB
Type II (Sony UX-S) 57 dB 65 dB 72 dB
Type | (Sony HF-S) 55 dB 63 dB 70 dB

(stereo phone jack)

(phono jacks) level impedance of 47
k ohms
Load impedance Over 10 k ohms
Headphones Output level 03 mW at a load

impedance of
32 ohms

Total harmonic distortion

100% (with Sony METAL-8LT
cassette)

Frequency response (DOLBY NR OFF)

Type IV cassette
(Sony METAL-8LT)

$046,000 HZ (13 dB)
30-4 4,000 Hz [0 VU(-4 dB) recording)

Type ll cassette
(Sony UX-S)

30-15,000 HZ (i3 (18)

Type I cassette
(Sony HF-S)

30-14000 Hz (:3 dB)

Wow and flutter

10.09 % W.Peak (lEC)
0.06% WRMS (NAB)
:0.1e% W.Peak (DIN)

General

Power requirements
Power consumption
Dimensions

Weight

120 V AC, 60 HZ

17W

Approx 430 X 123 x 300 mm (w/h/d)
(17 x 47/3 x 117/8 inches)
including projecting parts and

controls

Approx 4.6 kg (10 lbs 3 oz)

~ Continued on next page -

STEREO CASSETTE DECK
SONE

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TC-RX47O

Supplied accessory
Audio connecting cords (2)

Design and specifications subject to change without notice.

TABLE OF CONTENTS

Section M Page
Specifications .................................. 1
Safety Check~out ............................... 2
1. GENERAL

Identification of Front Panel Pans ~~~~~~~~~~~ 3
2. DISASSEMBLY ......................... 4
3. ADJUSTMENTS
3-]. Mechanical Adjustment -------------------- 6
3-2. Electorical Adjustments ~~~~~~~~~~~~~~~~~ 6
4. DIAGRAMS
4-1. Printed Wiring Board
4-2, Schematic Diagram ....................... 13
5. EXPLODED VIEWS ~~~~~~~~~~~~~~~~~~~~ 17
6. ELECTRICAL PARTS LIST ~~~~~~~~~~~~ 21

SAFETY-RELATED COMPONENT WARNINGII

COMPONENTS IDENTIFIED BY MARK A 0R DOTTED
LINE WITH MARK A ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL TO SAFE
OPERATION. REPLACE THESE COMPONENTS WITH
SONY PARTS WHOSE PART NUMBERS APPEAR AS
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.

SAFETY CHECK-OUT

After correcting the original service problem, perform
the following safety check before releasing the set to the
customer:

Check the antenna terminals, metal trim, metallized
knobs, screws, and all other exposed metal parts for AC
leakage. Check leakage as described below.

LEAKAGE TEST

The AC leakage from any exposed metal part to earth
ground and from all exposed metal parts to any exposed
metal part having a return to chassis, must not exceed 0.5
mA (500 microampers). Leakage current can be measured
by any one of three methods.

1. A commercial leakage tester, such as the Simpson
229 or RCA WT-540A, Follow the manufacturers
instructions to use these instruments.

2. A battery-operated AC milliammeter. The Data
Precision 245 digital multimeter is suitable for this
job.

3. Measuring the voltage drop across a resistor by
means of a VOM or battery~operated AC voltmeter.
The limit indication is 0.75 V, so analog meters
must have an accurate low-voltage scale. The
Simpson 250 and Sanwa SH-63Trd are examples of
a passive VOM that is suitable. Nearly all battery
operated digital multimeters that have a Z V AC
range are suitable. (See Fig. A)

To Exposed Metal
Parts on Set
F A0,
0.15 u v0 tmeler
1'5 kg (0. 75 V)

'2 Earth Ground

Fig. A. Using an AC voltmeter to check AC leakage.

ATTENTION AU COMPQSANT AYANT RAPPORT
A LA SECURITE!

Les COMPOSANTS IDENTIFIES PAR uwe MAROUE A
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POSANTS oue PAR DES Pieces SONY DONT Les
NUMenos sour DONNES DANS ce MANUEL ou
DANS Les SUPPLEMENTS PUBLIES PAR soNv.