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
" Never reuse a disconnected chip component.
" Notice that the minus side of a tantalum capacitor may be
damaged by heat.
TELEPHONE
MICROFILM
 1 
IT-B9
3-2. SCHEMATIC DIAGRAM " 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:
" All capacitors are in µF unless otherwise noted. pF: µµF
50 WV or less are not indicated except for electrolytics
and tantalums.
" All resistors are in &! and 1/4 W or less unless otherwise
specified.
" C : panel designation.
" U : B+ Line.
" Power voltage is dc 12 V and fed with regulated dc power
supply from JP1 with 100 &! in series.
" Voltage is dc with respect to ground under no-signal
condition.
no mark : OFF HOOK
( ) : ON HOOK
" Voltages are taken with a VOM (Input impedance 10 M&!).
Voltage variations may be noted due to normal produc-
tion tolerances.
" Signal path.
N : RX
O : TX
" Abbreviation
CND : Canadian model.
 7   8 
SECTION 4
EXPLODED VIEW
NOTE:
" IC Block Diagrams
" The mechanical parts with no reference
" -XX and -X mean standardized parts, so " 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
" Items marked  * are not stocked since
original one. the last of this parts list.
they are seldom required for routine service.
" Color Indication of Appearance Parts
U1 BA8206 U110 NJM2113M
Some delay should be anticipated
Example :
when ordering these items.
KNOB, BALANCE (WHITE) ... (RED)
Parts Color Cabinet s Color
CD 1 8 VOUT2
+
VCC 1
VREF 2 7 GND

AMP 8 OUT
+VIN 3 6
V+
POWER
SUPPLY
10
RSL 2
WITH
HFI
7
HYSTERESIS
+
 VIN 4  VOUT1
5
LFI 3 6 HFO
1
LOW
HIGH
FREQ.
FREQ.
OSC
OSC
LFO 4 5 GND
2
#1
#1
3
9
(including
12, JP50, T80)
X1
(not supplied)
6
U80 MC34118DW
JP50
11
4
(including X1)
28 27 26 25 24 23 22 21 20 19 18 17 16 15
A
R
400
A
BACK GROUND
SP110
NOISE MONITER
5
R LEVEL DET
VCC
BIAS
DP-DET

AGC
+
RX ATT
15mV
BACK GROUND VR
#3
NOISE MONITER 7
#2
ATT CONTROL
7
#2
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)
3 3-025-137-01 LEVER (HOOK) (GRAY) ... (GRAY,BLUE) 10 X-3376-495-1 HANDSET ASSY (BLUE)
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
 9   10 
N
N
V8
TU1
CPT
PU1
RX0
RX1
CPR
TLI2
GND
RLI2
TLO1
TLO2
PLO1
RLO2
FI
FO
CT
CO
TXI
NTI
Vcc
VCL
TXO
WCI
WCO
MUTE
HTO(+)
HTO( )

+