Technics SU-V2X Service Manual

@ CONTENTS
Page
PROTECTION CIRCUITRY .....-. 2.00.2 0s eevee nneee 2
BEFORE REPAIR AND ADJUSTMENT ..........22028. 2
LOCATION OF CONTROLS... .... 2.5.0 ee eee eee 2,3
DISASSEMBLY INSTRUCTIONS .............2..002. 4~6
TERMINAL GUIDE OF TRANSISTORS, DIODES AND IC’S.... 6
FUNCTION OF TERMINAL
1C601 (IcQ control)... ee 7
1C401 (Analog function control)... . 2... 2. ee ee 8
Mi PROTECTION CIRCUITRY
The protection circuitry may have operated if either of
the following conditions is noticed:
@ No sound is heard when the power is turned on.
@ Sound stops during a performance.
The function of this circuitry is to prevent circuitry
damage if, for example, the positive and negative speaker
connection wires are ‘‘shorted’’, or if speaker systems
with an impedance less than the indicated rated im-
pedance of this unit is used.
Page
CIRCUIT BOARDS AND WIRING CONNECTION
DIAGRAM). |.c3-605 Seetcce 5a Saree ee eek ae a 9,10
PRINTED CIRCUIT BOARDS ................00- 11~13
BLOCK DIAGRAM .... 2... 2.2... ee ee te ee 14,15
SCHEMATIC DIAGRAM ... 1... . . eee ee ee 16~20
RESISTORS & CAPACITORS .............00 00205 ae 21
REPLACEMENT PARTS LIST............ 02000 eu uue 22
EXPLODED VIEW iota ce eae ek Goa ae Oe ae 23, 24
If this occurs, follow the procedure outlines below:
1. Turn off the power.
2. Determine the cause of the problem and correct it.
3. Turn on the power once again.
Note
When the protection circuitry functions, the unit will not
operate unless the power is first turned off and then on
again.
M@ BEFORE REPAIR AND ADJUSTMENT
1. Disconnect AC power, Discharge both Power Supply Capacitors C701 and C702 (8200uF) through a 102, 5W resistor
to ground.
DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may distroy solid state devices.
2. After repairs are completed, restore power gradually using a variac, to avoid overcurrent.
Current consumption at 50/60Hz in NO SIGNAL mode should be shown below with respect to supply voltage 110V/
120V/220V/240V.
Power supply voltage AC110V
AC120V AC220V AC240V
Hi LOCATION OF CONTROLS
Operation indicator
Computer drive automatic indicator
Power switch
igirtbons
(bass)
Tone controls] |
(treble)
Tone switch ( HL defeat, = on)
Subsonic fitter switch ( HL off, = on}
170 ~360mA
90 ~ 200mA 80 ~180mA
Balance control
Audio muting switch ( off —»—20dB)
Loudness switch ( 9 off, = on)
Volume control
é Recording output
4}. signal indicator
{et Input signal
: indicator
Selectors
(tape 1/DA tape}
Recording mode switch
Recording mode indicator

Technics SU-V2X Specifications

General

Brand	Technics
Model	SU-V2X
Category	Amplifier
Language	English