IT-B9

SERVICE MANUAL

Canadian Model

E Model

Photo : Gray type

SPECIFICATIONS

Dial signal

Tone, 10 PPS (pulse) selectable Dimensions

Approx. 165.5 � 84 � 219 mm (w/h/d) (Approx. 6 5/8 � 3 3/8 � 8 5/8 inches) Mass

Approx. 530 g

(Approx. 1 lb. 3 oz.)

Supplied accessories

Telephone line cords (2) (Canadian) Telephone line cord (1) (E) Wall bracket (1) (Canadian) Design and specifications are subject to change without notice.

Notes on Chip Component Replacement

�ó Never reuse a disconnected chip component.

�ó Notice that the minus side of a tantalum capacitor may be damaged by heat.

TELEPHONE

MICROFILM

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IT-B9

3-2. SCHEMATIC DIAGRAM �ó Refer to page 9 for IC Block Diagrams.

CAUTION

FOR CONTINUED PROTECTION AGAINST FIRE, RE-PLACE ONLY WITH SAME TYPE SAME RATING FUSE.

REFER TO SERVICE PERSONNEL. (0.5A/125V) Note:

�ó All capacitors are in µF unless otherwise noted. pF: µµF

50 WV or less are not indicated except for electrolytics and tantalums.

�ó All resistors are in �"Ś and 1/4 W or less unless otherwise specified.

�ó C : panel designation.

�ó U : B+ Line.

�ó Power voltage is dc 12 V and fed with regulated dc power supply from JP1 with 100 �"Ś in series.

�ó Voltage is dc with respect to ground under no-signal condition.

no mark : OFF HOOK

(

) : ON HOOK

�ó Voltages are taken with a VOM (Input impedance 10 M�"Ś).

Voltage variations may be noted due to normal produc-tion tolerances.

�ó Signal path.

N

: RX

O

: TX

�ó Abbreviation

CND : Canadian model.

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SECTION 4

EXPLODED VIEW

�ó IC Block Diagrams

NOTE:

�ó The mechanical parts with no reference

�ó -XX and -X mean standardized parts, so

�ó Accessories and packing materials and number in the exploded views are not supplied.

they may have some difference from the hardware (# mark) list are given in

�ó Items marked �ś*” are not stocked since original one.

the last of this parts list.

they are seldom required for routine service.

�ó Color Indication of Appearance Parts U1 BA8206

U110 NJM2113M

Some delay should be anticipated Example :

when ordering these items.

KNOB, BALANCE (WHITE) ... (RED) N

N

Parts Color Cabinet’s Color CD

1

8

VOUT2

VCC 1

+

VREF

2

7

GND

AMP

8 OUT

–

+VIN

6

POWER

3

V+

SUPPLY

RSL 2

10

WITH

7 HFI

HYSTERESIS

+

–VIN

4

–

5

VOUT1

LFI 3

6 HFO

1

LOW

FREQ.

HIGH

OSC

FREQ.

LFO 4

OSC

5 GND

2

#1

#1

3

9

(including

12, JP50, T80)

X1

(not supplied)

U80 MC34118DW

6

JP50

GND

CPR

PU1

PLO1

TLO1

TU1

RX0

RX1

RLI2

RLO2

TLO2

TLI2

CPT

V8

4

11

28

27

26

25

24

23

22

21

20

19

18

17

16

15

(including X1)

A

R

400

BACK GROUND

A

SP110

NOISE MONITER

5

R

LEVEL DET

VCC

BIAS

DP-DET

–

AGC

+

RX ATT

15mV

BACK GROUND

VR

#3

NOISE MONITER

7

ATT CONTROL

#2

#2

7

8

T80

12

#1

LEVEL DET

TX ATT

VR

Ref. No.

Part No.

Description

Remark

Ref. No.

Part No.

Description

Remark

VR

FILTER

R

+

–

+

–

1

3-025-136-01 HANGER (HANDSET) (GRAY) ... (GRAY,BLUE)

* 8

1-670-811-11 KEY BOARD

R

+

–

1

3-025-136-11 HANGER (HANDSET) (CREAM)

* 9

A-3672-566-A MAIN BOARD, COMPLETE (Canadian)

–

+

2

3-025-132-01 CABINET (UPPER) (GRAY)

* 9

A-3672-571-A MAIN BOARD, COMPLETE (E) VR

2

3-025-132-11 CABINET (UPPER) (CREAM) 10

X-3376-493-1 HANDSET ASSY (GRAY) 1

2

3

4

5

6

7

8

9

10

11

12

13

14

2

3-025-132-21 CABINET (UPPER) (BLUE) 10

X-3376-494-1 HANDSET ASSY (CREAM) FO

FI

CO

Vcc

NTI

CT

TXO

TXI

WCO

WCI

VCL

MUTE

3

3-025-137-01 LEVER (HOOK) (GRAY) ... (GRAY,BLUE) 10

X-3376-495-1 HANDSET ASSY (BLUE) HTO(+)

HTO(–)

3

3-025-137-11 LEVER (HOOK) (CREAM) 11

X-3376-481-1 CABINET (LOWER) ASSY (Canadian:GRAY) 4

3-025-134-01 BUTTON (12 KEY) (GRAY) ... (GRAY,BLUE) 11

X-3376-482-1 CABINET (LOWER) ASSY (E:GRAY) 4

3-025-134-11 BUTTON (12 KEY) (CREAM) 11

X-3376-483-1 CABINET (LOWER) ASSY (E:CREAM) 5

1-771-515-11 SWITCH, RUBBER KEY

11

X-3376-484-1 CABINET (LOWER) ASSY (E:BLUE) 6

1-765-574-11 CORD, CURL (CREAM) 12

3-025-138-01 CAP, MICROPHONE

6

1-775-798-31 CORD, CURL (BLUE) JP50

1-785-426-11 JACK, MODULAR (4C) 4P (HANDSET) 6

1-775-798-41 CORD, CURL (GRAY) SP110

1-529-151-11 SPEAKER (5.7cm) 7

3-025-139-01 FOOT, RUBBER

T80

1-542-368-11 MICROPHONE, ELECTRET CONDENSER

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