Sony tc wr 80 es service manual

Page 2

TC-WR80ES/WR820A

FEATURES

0 The Dolby HX PRO* system which improves the
linearity of a tapes high-range response during
recording.

0 Automatic tape type detection during playback and
recording.

. A relay Iunctlon for long playback.

o Auto-synchro dubbing at normal or high (double)
speed.

- AMS and memory play functions which provlde easy
access to desired selections.

0 An easy-to-read linear counter which shows the
elapsed recording or playback time for decks A and B.
(WRSOES)

0 An easy-to-read digital counter equipped with a
memory function (for decks A and B). (WR820A)

Dolby noise reduction and HX Pro headroom extension manufactured
under Ilcense from Dolby Laboratories Licensing Corporation HX Pro
originated by Bang 8. Olutsen.

DOLBY, the double-D symbol DD and HX PRO" are trademarks
of Dolby Laboratories Licensing Corporation.

SAFETY CH ECK-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.

I. A commercial leakage tester, such as the
Simpson 229 or RCA WT-S40A. Follow the
manufacturers instructions to use these instru<
ments.

to

A batterycperated 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 volt-
meter. The limit indication is 0.7SV, 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 at 2V AC range are '
suitable. (See Fig. A)

Ta Exposed Metal
Parts on Set

AC
0.15uF glint voltmerer
{0.75 VI
- l

-_J

". Earth Ground

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

SAFETY-RELATED COMPONENT WARNINGII

COMPONENTS IDENTIFIED BV MARK A OR 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.