1
SERVICE MANUAL
Canadian Model
E Model
IT-B9
TELEPHONE
MICROFILM
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.
Photo : Gray type
2
SECTION
1
GENERAL
This
section
is
e
xtracted
from
instr
uction
manual.
3
4
SECTION 2
DISASSEMBLY
Note : Follow the disassembly procedure in the numerical order given.
2-1. CABINET (LOWER)
2-2. KEY BOARD
2-3. MAIN BOARD
1 JP2
2 BTP 2.6X6
3 BTP 2.6X6
4 MAIN board
5 modular jack
1 BTP 3X10
2 BTP 3X10
3 JP110
1 cabinet (lower)
1 BTP 2.6X6
2 KEY board
3 rubber key switch
4 button (12 key)
3-1. PRINTED WIRING BOARDS
IT-B9
Note:
· X : parts extracted from the component side.
·
: Carbon pattern
· b : Pattern from the side which enables seeing.
· Abbreviation
CND : Canadian model.
5
6
SECTION 3
DIAGRAMS
Ref. No.
Location
D1
B-9
D2
B-9
D3
B-10
D4
B-10
D5
B-8
D10
B-12
D11
B-12
D12
C-12
D13
B-12
D14
D-11
D15
E-9
(D16)
C-12
D30
F-9
D33
G-12
D39
F-8
D40
E-7
D91
E-8
LED20
G-4
Q10
C-12
Q11
C-12
Q12
C-11
Q20
D-12
Q30
F-7
Q31
F-7
Q32
E-8
Q33
F-9
Q50
D-9
Q51
E-9
Q52
D-9
Q53
D-7
Q54
C-7
Q55
C-8
Q80
F-12
U1
C-9
U30
F-8
U80
G-10
U110
E-11
ZD1
B-9
ZD10
D-11
ZD50
D-10
ZD51
D-10
ZD52
C-8
ZD53
C-8
· Semiconductor
Location
(
) : Canadian Model
3-2. SCHEMATIC DIAGRAM · Refer to page 9 for IC Block Diagrams.
IT-B9
7
8
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.
CAUTION
FOR CONTINUED PROTECTION AGAINST FIRE, RE-
PLACE ONLY WITH SAME TYPE SAME RATING FUSE.
REFER TO SERVICE PERSONNEL. (0.5A/125V)