Canon Cat Repair Manual page 65

3-4. CPU PCB Unit
Waveform Observation Conditions
Connect the telephone and the line to the jacks respectively. and observe
the following waveforms.
®
Ring tone signal at answering
@ Waveforms when .ettillg Dial Pulse "3" at transmission to Auto Dial
@
Ring tone signal at answering
@ Waveforms do not appear during the standby period.
The waveforms can only be seen during DTMF operation.
These waveforms are generated when the DTMF tone is used for Auto
Dial.
®
Waveforms when the DTMF tone for automatically dial "2".
CD
Waveforms when the carrier is received 1200 bps: PSK
®
Waveforms when the carrier is received 300 bps: FSK
@
Receiving carrier and waveforms after demodulation
3-40
®
@
@
SOURCES CHI
CH2
@
TEST POINT 701 702
VOLT/DIV
50V DC 58'l DC
TlME/DIV
0.1 s
TRIGGER CHi.J
GID
GND
SOURCES CHI CH2
®
TEST POINT
701 702
VOLT/DIV 20V DC 20V DC
TIME/DIV 0.1 s
TRIGGER
CHI,
GID
GND
SOURCES
CHI CH2
CD
TEST POINT 703
704
VOLT/DIV
20V AC 2V DC
TIME/DIV 0.1 s
TRIGGER CHI.-!
~-;~.W·"i":i
@)
GND .... ...,..., ..
! . . . .
' ! ' " -t-I.(.l ..
r~
. .
ll~
. . . .
H.I ..........
~
SOURCES CHI CH2
TEST POINT 801 802
VOLT/DIV
5V DC 5V DC
TIME/DIV 100
TiS
TRIGGER CHI,
SOURCES CHI CH2
TEST POINT 803 804
VOLT/DIV
2V DC 2VDC
TIME/DIV 20 ms
TRIGGER CHI ""1
SOURCES
CHI CH2
TEST POINT 901 902
VOLT/DIV 2V AC 2V AC
TIME/DIV 0.2 ms
TRIGGER CHI,
~
....
~~~
..... ' 1 I, f 1 I I I I
-:1\;1
@) ....
;--+...\,i.~
...
GND
~./.i
...
r ' t
®
SOURCES
CHI CH2
TEST POINT 901 902
VOLT/DIV O.W AC 2V AC
TIME/DIV
0.2 ms
TRIGGER
CHI"
@)
GND .... •
@).lQt~
GND ....
Vr·~<=
f~:--~ ,
®
SOURCES CHI
CH2
TEST POINT 903 904
VOLT/DIV
0.2V AC 5V DC
TIME/DIV 2 ms
TRIGGER
CH2.J