XW-HT1
57
5
6
7
8
5
6
7
8
C
D
F
A
B
E
7.1.3 POWER ON SEQUENCE
Check the circuits around Q3305
and Q3511.
Is Pin 5 of IC3302
"H" and Pin 6 "L"?
No
No
Yes
Check the audio lines to narrow
down the point in failure.
It is most likely that the RX module
or TX section is in failure.
The +B and ground circuits are
most likely to be short-circuited,
or IC3302 is likely to be broken.
Detach the
RX module, then by
inputting an audio signal to the
jumper lead for servicing,
check if sound is
output.
No
sound
Sound is output.
Are the protection
circuits in IC12 and
IC13 broken?
Yes
To diagnosis of the TX section
RX side
(2-2) In a case where no sound is output
•
A pin number is a terminal number of
the system microcomputer PDC 118.
XRESET (Pin 2) terminal is set to Hi.
TEST (Pin 4) terminal is Lo, it will become line test mode.
It is a communication start because of initialization
of VOLUME IC. (43,44,45pin)
SRESET (Pin13) terminal is set to Hi.
DSP IC and a communication start. (9,10,11,12pin)
In the power ON, it is each MUTE
release after about 5 seconds.
XSYSMUTE (38pin) terminal is Hi.
XWMUTE (42pin) terminal is Hi.
XSWMUTE (37pin) terminal is Hi.
However, when volume is "0", it does not cancel MUTE.
RESET START
Line test mode
distinction
Intitialization of the
VOLUME IC(IC1751)
DSP starting
Canceling of
MUTE
POWER ON
Intitialization of the
system microcomputer
Summary of Contents for XW-HT1
Page 35: ...XW HT1 35 5 6 7 8 5 6 7 8 C D F A B E H 4 4 H 2 4 H 2 4 ...
Page 47: ...XW HT1 47 5 6 7 8 5 6 7 8 C D F A B E SIDE B SIDE B G G TX MODULE G H10 H2 U23 ...
Page 49: ...XW HT1 49 5 6 7 8 5 6 7 8 C D F A B E SIDE B SIDE B H H RX MODULE H CN3701 C H3 ...
Page 72: ...XW HT1 72 1 2 3 4 1 2 3 4 C D F A B E NJU26150 DSP ASSY IC1301 DSP IC Pin Function ...
