Akira HTS 898 266 -Home Theatre System – Circuit Diagram – Troubleshooting
TROUBLE SHOOTING
Cracking, Small sounds
Analyse:
A) If the input signal accompany with direct current, it possibility strikes the selecting IC CD4052, then cause the sounds cracking, and small.
B) The electrolytic capacitor 47uF/50V of center and surround output is invalidation by the effects of temperature and humidity.
C) The possible damage parts : CD 4052 and PT2253
1. PT2253 function : Volume control
2. CD4052 function : Dual 4-channel Analog Multiplexer
D) Testing whether the IC CD4052\PT2253 power supply ( +5.1V ) is natural.
Solution: Change damage parts.
Circuit Diagram
Hum
sounds
Analyse:
Filter electrplitic capacitor 3300uF/50V will be invalidation when it is at high voltage or high temperature and humidity
Solution: Change damage capacitor 3300uF/50V.
Analyse:
Filter electrplitic capacitor 3300uF/50V will be invalidation when it is at high voltage or high temperature and humidity
Solution: Change damage capacitor 3300uF/50V.
VFD
display damage
Analyse:
a. Due to the working voltage of VFD is connecting to the transformer, if the voltage is too high, easy be burn out the VFD display.
b. The filament of the display is fried, so must avoid to strong shock, or more
c. easy mangles the display.
d. The possible damage parts: VFD display, electrolytic capacitor 470uF/50V and diode IN4004.
e. Testing whether the power from transformer to the front panel controller is normal, AC22V and AC6V.
Solution : Change new parts instead of the damage parts.
After repairing, momentarily power on, observing whether the VFD is abnormality.
Analyse:
a. Due to the working voltage of VFD is connecting to the transformer, if the voltage is too high, easy be burn out the VFD display.
b. The filament of the display is fried, so must avoid to strong shock, or more
c. easy mangles the display.
d. The possible damage parts: VFD display, electrolytic capacitor 470uF/50V and diode IN4004.
e. Testing whether the power from transformer to the front panel controller is normal, AC22V and AC6V.
Solution : Change new parts instead of the damage parts.
After repairing, momentarily power on, observing whether the VFD is abnormality.
Front
panel loses control, can not choose the input signal
Analyse:
a. Be interfered by strong electromagnetism or wavy power supply.
b. The working voltage is too high, or IC BA5049/LM324 is losing control by the temperature and humidity.
c. The possible damage parts : IC BA5049, CD4052 and LM324.Front panel.
Analyse:
a. Be interfered by strong electromagnetism or wavy power supply.
b. The working voltage is too high, or IC BA5049/LM324 is losing control by the temperature and humidity.
c. The possible damage parts : IC BA5049, CD4052 and LM324.Front panel.
IC BA5049 function : Remote receiver and decoder
CD4052 function : Dual 4- Channel Analog Multiplexer
LM324 function : Quad Operational Amplifier, VFD display driver.
CD4052 function : Dual 4- Channel Analog Multiplexer
LM324 function : Quad Operational Amplifier, VFD display driver.
Solution:
Testing whether the IC working voltage (+5.1V) is natural.
Change new parts to instead of the damage parts
Place the player in the place without electromagnetism interfering.
Operate the player at a steady-voltage.
Testing whether the IC working voltage (+5.1V) is natural.
Change new parts to instead of the damage parts
Place the player in the place without electromagnetism interfering.
Operate the player at a steady-voltage.
Analyse:
a. Refer to Amplifier Diagram to change the possible damage parts which caused by C5196
burnout. (Test by digital multimeter to make judgement whether the parts are workable or
not)
b. Series-wound connect one 40W bulb at the wavy power supply 220V/240V, it will react on protecting when you are repairing.
c. C). Make sure changed all of the damage parts, then, power on.
d. If the 40W bulb suddenly shinny, then fades slowly ( It indicates that the player is work normally). If the bulb is shinny all the way, then there is still some short circuit on the PBC, recheck there is any other damage parts).