akira HTS-797AS, Руководство по обслуживанию

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Model No.: HTS-797AS
Version: 1.0
B
A
NO
NO
NO
YES
YES
YES
YES
NO
NO
YES
YES
NO
NO
YES
Signal check is all right but there is
no output
Whether U701 (37) power supply
is normal (about 10v)
10V Check the 10v
power supply circuit
Whether MUTE is
low level
NO
Check CPU and the I/O
connection
Q709 NG
YES
Whether U701 (38)
(39) (40) have data
pulse signal
Q709 NG
Check CPU (32) to see
whether it is low level
Q009 NG
CPU NG
Whether U701 (9) (10) (11)
(12) (13) (14) have output
U701 NG
Whether U702, U703,
U704 (1) (7) have output.
Check
±
12V power
supply circuit
Whether R502 terminal has
output
Check the signal
detection and the MUTE
circuit
Check VH ± and VL ± to
see if they are normal
Whether U701 (35) is high
level
YES
YES
NO
YES
YES
NO
YES
NO
NO
YES
NO
NO
YES
NO
There is no signal output t (take
DVD channel for example)
Switch to DVD channel U801 (3)
(13) to see if there is output
Whether U801 (7)
(16) ± 6V power
supply is normal
Check ± 6V
power supply
circuit
Whether U801 Select-A is 0V
and Select-B is 5V
The signal’s check
circuit has
problems. Check the
compare Circuits
Check the output of U701 (42)
(43) Select to see if it is normal
Check the GROUND of
U801, U802, U803 to see
if it is ok
Check the printed circuit
between U701 and U801
Check the power supply of U701
（ 37 ） to see if it is 10v or so
Check the 10v
power supply circuit
Whether U701 (38) (39) (40)
have the data pulse input
U701
Whether CPU U001 (33) (34)
(35) have the data pulse input
The I/O connection
between U001 and U701is
at open state.
CPU or its affiliated circuit is
damaged.