Sony tc w 320 service manual

Page 2

TC-W320/W3ZOS/WR520/WR5208

SAFETY CHECKoOUT MODELIDENTIFICATION TC-W320
.. . TC-WSZOS

(Specification Label) TC-WR520
After correcting the original service problem, TC-WR5203

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 _s ONYQ MODEL N0. 2%
AC leakage. Check leakage as described below.

STEREO CASSETTE DECK

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 US' Canadian model: AC120V SOHZ 23W
methods_ UK model: Ac24ov ~50/60Hz
. WG, AEP model: AC220V ~50/60HZ

I. A commerctal leakage tester, such as the E model: A0120, 220' 240V ~50/60HZ

Simpson 229 or RCA WT-540A. Follow the
manufacturers instructions to use these instru-

ments. Operating voltage
Operate the unit on either 120. 220 or 240 V AC, 50/60
2. A battery-Operated AC milliammeter. The Data Hz. Belore connecting the unit to the power source.
Precision 245 digital multimeter is suitable for check that the operating voltage oi your unit is the same
this job. as the local power line voltage.

The voltage selector is located on the rear panel. It the
selector must be reset. disconnect the AC power cord
and set the selector to the appropriate voltage.

3. Measuring the voltage dmp across a resistor by
means of a VOM or battery-operated AC volt-
meter. 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 VOLTAGE
multimeters that have a 2V AC range are
suitable. (See Fig. A)

VOLTAGE Selector

220V

240V

120V

To Exposed Metal
Parr: on Set

SAFETYsFIELATED COMPONENT WARNING
COMPONENTS IDENTIFIED BY MARK A OR DOTTED
LINE WITH MARK A ON THE SCHEMATIC D|AGRAMS
. AND IN THE PARTS LIST ARE CRITICAL TO SAFE

Ac OPERATION. REPLACE THESE COMPONENTS WITH
0.15uF gum / voltmeter s0Nv PARTS WHOSE PART NUMBERS APPEAR As
(0J5V/ suown IN THIS MANUAL on IN suPPLEMENTs PUE-

' LISHED BY SONY.

ATTENTION AU COMPQSANT AYANT RAPPORT
A LA SECURITE!

Fig. A. Using an AC voltmeter to check AC leakage LEs COMPOSANTS IDENTlFlEs PAR UNE MARQUE A
sun LES DIAGRAMMES SCHEMATIOUES ET LA 1.:er
oes PlEcEs SONT cmTlouEs FOUR LA SECURITE
oE FONCTIONNEMENT. NE REMPLACER cas COM-
POSANrs au: PAR DES PlEcEs SONY DONT LES
NUMEROS som DONNEs DANS CE MANUEL ou
DANS LES SUPPLEMENTS PUBLIES PAR SONY.

'é" Earth Ground