Roadstar DVR-9100, Руководство по обслуживанию, Страница: 18 / 76

16
TROUBLE SHOOTING
D. The sound of TV-tuner audio L/R channel not functionally normally
R/L audio error
Check the flat cable
connected to the main
board to see if it’s secured
to the right socket.
Use TV cable or signal
generator to input TV
signal.
Measure
the voltage on pin5
and pin6 on U103 with a
multimeter if it’s 5v or
32v
Check the resistors,
capacitors and inductors
near U103 for short circuits
or bad soldering.
Check positions U3 and JP1
on the main board or any
resistors near the IC for short
circuit or bad soldering.
Use the oscilloscope to measure the voltage
output on pin6 &pin7 on JP1. The range of
the voltage is between 2~2.3V.(This is the
standard value; need to compare the value
with the customer’s request. So far, there’s
another value about 1V.
Check
positions J3,J45,
U12~U15,U20,U21,U24
the main board or any resistors
or capacitors nearby for short
circuit or bad
soldering.
Change U103
Change the TV-tuner board on JP1
No
Yes
Yes