Sony str av 720 service manual

Page 1

SERVICE MANUAL

US Model

Canadian Model

Austral/an Model

SPECIFICATIONS
AUDIO POWER SPECIFICATIONS Amp'i'ie' m"
S/N PHONO MM 87 dB
POWER OUTPUTAND TOTAL HARMONIC "3 (5")
DAT, CD VIDEO 1,2 105 dB
DISTORTION TAPE 1.2 85 dB' (A,150mVl
, , Output sensitivity/ DAT OUT
With 8-ohm load, both channels driven, from impedance TAPE our 1,2 132(32)me
20 - 20,000 Hz, rated 80 watts per channel $51 Isns A k f
. I . cce IS 59
minimum RMS power, With no more than 8-15m: erso
0.08% total harmonic distortion from 250 HEADPHONES Accepts
- ' headphones of high
mIIIIwatts to rated output. and low impedance
TONE controls BASS: :10dB at
. . . 100 Hz
Other Specmcations TREBLEj :1ch a1
tokHz
Amplifier section MUTING , 20dB
Dynamic power 8 ohms, at 1 kHz IHF 110 + 110 watts DBFB +10 dB (70 Hz)
WW 4 ohms, at 1 kHz IHF 140 + 140 watts _ . '7BIHF
Harmonic distortion at rated output Less than 0.08%
lnterrnodulation (IM) distortion at rated Less than 008 % Video sectioy-I
output
, , Inputs VIDEO 1.2: t Vp-p 75 ohms
P d If h , 20 n
33:;ngan °f sur'oun amp ' '8 (8 0 ms (1 OWE: was) Outputs VIDEO 1, MONITOR: 1 Vp-p 75 Ohms
Frequency response equalization curve
PHONO RIAA : 0.5 dB
SEjEEgI'zTAPE 2 10 Hz - 50 kHz :goa
Residual noise Less than aouv
Damping iactor (8 ohms. at 1 kHz) 40 7 continued on next page 7
Input sensitivity/ PHONO MM 25 mV, 50 kilohms
'mpedance DAT,CD. VIDEO 1,2 150 mV
TAPE 1,2 50 kilohms

FM STEREfl/FM-AM RECEIVER

SONY;

Page 2

STR-AV720

FM tuner section

Frequency range

87.5 -108.0 MHZ

Antenna terminals

800 ohms. balanced
75 ohms. unbalanced

Sensitivity at 50 dB

18.3 dBt. 4.5 ,ILV (mono)
38.3 dBl. 45 51V (stereo)

Usable sensitivity 11.2 wit. 2 iiV (lHFl
S/ N Mono 80 dB
Stereo 74 dB
Harmonic Mono 0,3 %
distortion at 1 kHz Stereo 05 %
IM distortion Mono 0.3 %
Stereo 0.5
Separation 45 dB at 1 kHz
Frequency response 30 Hz - 15 kHz :2 dB
Selectivlty 60 dB a1400 kHz
Capture ratio 12 dB
AM suppression ratio 54 dB
lmage response ratio 70 dB
IF response ratio 70 dB
Spurious response ratio 80 dB
RF intermodulation at 800 kHz 60 dB
Auto tuning Low 30 mil
threshold High 50 dB!

SAFETY CH ECK-OUT

AM tuner section

Frequency range

USA and Canadian model:
530 - 1710 kHz (with 10 kHz interval)
531 -- 1710 kHz (with 9 kHz interval)
Australian model: 531 - 1710 kHz

Antenna

Loop antenna

Usable sensitivity

50 dB/m (at 1.000 kHz or 999 kHz)

SIN

54 dB (at 50 mV/m)

Harmonic distortion 0.5% (50 mV/m, 400 Hz)

Selectivity

35 dB (9 kHz), 40 dB (10 kHz)

Auto tuning threshold 55 dB/m

General
System Tuner section PLL quartz-locked digital synthesizer
system
Preamplifier Low-noise NF type equalizer
section
Power amplilier Quasivcomplimentary SEPP
secnon

Power requirements

USA and Canadian models:

120 V AC, 60 HZ
Australian model: 240 V AC. 50/60 Hz

Power consumption

USA model: 190 watts
Canadian model. 360 VA
Australian model: 200 watts

AC outlets (USA and
Canadian models only)

Two switched, total 100 watts

Dimensions 430 X 135 x 350 mm
(17 x 53/8 x 141/8Inches)
Weight USA and Canadian model: 9.5 kg (21 lb)

Australian model: 9,8 kg (21 lb 10 oz)

Supplied accessories

FM ribbon antenna (1)

AM loop antenna (1)

Remote commander (1) RM-8103
Sony Batteries SUM-3(NS) (2)

Design and specifications subject to change without notice.

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.

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

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 volt-
meter. The limit indication is 0.75V, 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 2V AC range are
suitable. (See Fig. A)

To Exposed Metal
Part: on Set

AC
0.75MF «I: £15142 ( voltmeter

(0.75 V}
1" Earth Ground

l

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

SAFETY-RELATED COMPONENT WARNING

COMPONENTS IDENTIFIED BY MARK A OR DOTTED
LINE WITH MARK & 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.