Jvc 4VN 990 Service Manual

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Jvc 4VN 990 Service Manual

Extracted text from Jvc 4VN 990 Service Manual (Ocr-read)


Page 2

PACKING ILLUSTRATION

E38608-121-©
CORNER PAD

E38608-121- 6)
TOP PAD

d
. E38608-121-@
, / CENTER PAD

E38608-121-@
INSIDE CASE

E38608-121-©

BOTTOM PAD
Fig. 1
Parts No. Parts Name Dwg. No. 1
L 4VN-990-PK Carton Case 4
4VN-990-NZ Packing Material 1,2,3,6
E32332-016 Envelope (for Set) -

EXPLODED VIEW OF MECHANICAL PARTS

Dwg. No. Parts No. Parts Name

1 E21 149-001 Cover

2 Q03093-108 Washer

3 SDSP4008NS Screw

4 E21199-001 Bottom Plate

5 LPSP4008NS Assy Screw

6 Q0591 1 -1 Foot

7 SBSB3010M Tapping Screw I
4VN-99O - 2 -

Page 38

POWER TRANSFORMER VOLTAGE

RED BLU
BLK \ GRN
RED YUW
GRN ORN
GRN RED
BLU BRN
BLU

26V RED 0 <9 BLU 120V
3.5A BLK C g 0 GRN IOOV
26V RED

YLW 0V
35V GRN a ORN 120V
0.3A GRN or 0 RED IOOV
5' BL Z:
0.5A BLU BRN 0V

Fig. 37

PROTECTOR ADJUSTMENT

The protector circuit dosent operate at 40 load, 14V output. (All channels are driven).

Adjust the R522 in order to actil activate the protector circuit by grounding the speaker terminals when the out put is
2 volt at 89. load.

And adjust R513 in order to activate the protector circuit by appling DC 0.25 volt to point A.

VU METER control adjustment

PROTECTOR CIRCUIT
TAC - 2 80

V V
R522 R514

METER common. cmcunr
TA C -250

V5 V v V
R603 R601 R602 R601.

CONTROL VOLUME
Fig. 38

4VN-990 _ 38 _.