Technics SUG 70 Service Manual

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SU-G7O

CONTENTS _

. _ Page
$=.ETYRRECAUTION,.' » A. . 12~1.4_.
BEFORE REPAIR ...... _ SCHEMATICD GRAM 15:22
PHOTEGTION CIRCUITFIY .............................. DESCRIPTION OF FL PANEL 23
ACCESSORIES ....................................... WIRING CONNECTION DIAGRAM . ..... 24 _
LOCATION OF CONTRoLs , , PRINTED CIRCUITBOARDs .. 25~23
CONNECTIONS ...... _ ........... , , . 5 REPLACEMENT PARTS LIST . .......... 29~32, 35
REMOTE-CONTROLOPERATION ........................ e~e EXPLODED VIEW ., ....................... 33,34
DISASSEMBLY INSTRUCTIONS ........................ 9~12

I SAFETY PRECAUTION UhISsafety precautlo I

. Before servicing, unplug the power cord to prevent an electric shot: . . »

. When replacing parts, use only manufacturer's recommended components for safety.

. Check the condition of the power cord, Replace if wear or damage is evident.

. After servicing, be sure to restore the lea-j dress, insulation barriers. insulation papers, shields, etc.

. Before returning the serviced equirment to the customer, be sure to make the following insulation resistance test to
prevent the customer from being exposed to a shock hazard.

Uwa-fi

o INSULATION RESlSTANCE TEST
1- Unplug the power cordJsind short the two prongs of the plug with a jumper wire.
2. Turn on the power w. .tch.
3. Measure the rfiistance value with ohmmeter between the jumpered AC plug and each exposed metal cabinet part, such as
c .. . Afaewhead}, antenna, control shafts, handle brackets, etc. Equipment with antenna terminals should read between SMSI
and séivmto all exposed parts. (Fig. A) Equipment without antenna terminals should read approximately infinity to
all exposed pans. (Fig. 8) ' . ~
Note: Some exposed parts may be isolated from the chassis by design. These williread infinity,

Antenna.
terminal I
: .

Exposed , , Exposed
; metal g metal
z part . part
F
5 Onmmeter Ohmmeter

(Fig-A) 3*, (Fig. 3)
fig Resistance = 3 _ .ZMQ , Resistance = Approx co '

4. If thefmeasurement is outside the specified limits, there is a possibility of a shock hazard. The equipment should be
repaired and rechecked before it is returned to the customer. '

- BEFORE REPAIR

(1) Turn oil the power supply. Using a 100. 10W resistor, connect both ends of power supply capcitors(C701, C702) in order
10 d charg e the voltage.

urning the power supply on, alter completion ol repair. slowly apply the primary voltage by using a power supply
volt e controller to make sure that the consumed current at 120V, 69Hz in NO SIGNAL mode is 430 mA~680 mA.