Check Point About Badness Stb - Strong SRT4375 Service Manual

The remote controller
Does not working.

5.2. Check point about badness STB

5.2.1. When nothing appears on TV screen(front panel display "0000")
(1) Check the SMPS's voltage
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Action) : If voltage is not normalcy, it change, and measure again SMPS
(2) Confirm that R32's voltage becomes 3.3V
Action) : If 3.3V is not normalcy in R32, if more than 100 ohm comes
(3) Confirm by Oscilloscope whether 27 MHz break out in R29 and R33.
Action) : if 27Mhz do not break out, X1(27Mhz CRYSTAL), or
(4) ROM Read
Oscilloscope at Power off/on in pin 26 of U2(39vf800A Flash ROM).
(If U2's pin 26 is 3.3V by Voltage Meter, it is normalcy)
Action) : if U2-pin26 is measured (0V ~ 2V) by Voltage Meter,
(5) Flash-Rom of Start Control Signal uses reset, chip-Select
The batteries of the
Remote controller are
Not inserted or
Exhausted.
Power Connect(J150) -> pin1, pin 2, pin 4 : 4.75~5.25V
Power Connect(J150) -> pin5
Power Connect(J150) -> pin7
Power Connect(J150) -> pin8
Power Connect(J150) -> pin10
first. Still, SMPS is normalcy if voltage is low.There are
possibility that is badness with parts that use the voltage in
Main Board.
when measured resistance value between R32 and GND after
do AC POWER OFF normalcy . On this time, change U150(3.3V
REGULATOR).
U5(74LCX04) change .
cycle(Pulse)
U2(39VF800A FLASH ROM) change, still, change U1(L64108
CPU) if do not act.
Check whether the batteries
Are inserted correctly in your
Remote controller.
Check the batteries, and if
Exhausted, replace the
Batteries of the remote
Controller.
: 10.2~12.6V
: 21V~24V
: 27V ~ 33V
: 7.5~8.5V
should be happened continuously through