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#1
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My Speaker has no power,it doesn't start
I have a midialnd MLI 480 computer speaker.
In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! |
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#2
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My Speaker has no power,it doesn't start
mars wrote:
I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. -- ================================================== ====================== Michael Kesti | "And like, one and one don't make | two, one and one make one." | - The Who, Bargain |
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#3
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My Speaker has no power,it doesn't start
mars wrote:
I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. -- ================================================== ====================== Michael Kesti | "And like, one and one don't make | two, one and one make one." | - The Who, Bargain |
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#4
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My Speaker has no power,it doesn't start
mars wrote:
I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. -- ================================================== ====================== Michael Kesti | "And like, one and one don't make | two, one and one make one." | - The Who, Bargain |
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#5
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My Speaker has no power,it doesn't start
mars wrote:
I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. -- ================================================== ====================== Michael Kesti | "And like, one and one don't make | two, one and one make one." | - The Who, Bargain |
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#6
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My Speaker has no power,it doesn't start
The speaker uses an AC adapter, and the label on the ac adapter said
it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. |
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#7
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My Speaker has no power,it doesn't start
The speaker uses an AC adapter, and the label on the ac adapter said
it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. |
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#8
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My Speaker has no power,it doesn't start
The speaker uses an AC adapter, and the label on the ac adapter said
it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. |
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#9
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My Speaker has no power,it doesn't start
The speaker uses an AC adapter, and the label on the ac adapter said
it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. |
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#11
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My Speaker has no power,it doesn't start
(mars) wrote in message . com...
The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? |
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#12
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My Speaker has no power,it doesn't start
(mars) wrote in message . com...
The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? |
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#13
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My Speaker has no power,it doesn't start
(mars) wrote in message . com...
The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? |
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#14
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My Speaker has no power,it doesn't start
(unitron) wrote in message . com...
(mars) wrote in message . com... The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? Yes,same reading. |
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#15
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My Speaker has no power,it doesn't start
(unitron) wrote in message . com...
(mars) wrote in message . com... The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? Yes,same reading. |
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#16
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My Speaker has no power,it doesn't start
(unitron) wrote in message . com...
(mars) wrote in message . com... The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? Yes,same reading. |
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#17
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My Speaker has no power,it doesn't start
(unitron) wrote in message . com...
(mars) wrote in message . com... The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? Yes,same reading. |
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#18
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My Speaker has no power,it doesn't start
(mars) wrote in message . com...
(unitron) wrote in message . com... (mars) wrote in message . com... The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? Yes,same reading. Finally, i know why my speaker is dead.Last night, i did a visual check and coutinuity test and i found out a cold solder joint at one pin of the switch(the switch is inside the glued wood case, so it is very tricky to see and test the switch) Anyway, Thank you for all of the help!!! |
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#19
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My Speaker has no power,it doesn't start
(mars) wrote in message . com...
(unitron) wrote in message . com... (mars) wrote in message . com... The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? Yes,same reading. Finally, i know why my speaker is dead.Last night, i did a visual check and coutinuity test and i found out a cold solder joint at one pin of the switch(the switch is inside the glued wood case, so it is very tricky to see and test the switch) Anyway, Thank you for all of the help!!! |
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#20
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My Speaker has no power,it doesn't start
(mars) wrote in message . com...
(unitron) wrote in message . com... (mars) wrote in message . com... The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? Yes,same reading. Finally, i know why my speaker is dead.Last night, i did a visual check and coutinuity test and i found out a cold solder joint at one pin of the switch(the switch is inside the glued wood case, so it is very tricky to see and test the switch) Anyway, Thank you for all of the help!!! |
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#21
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My Speaker has no power,it doesn't start
(mars) wrote in message . com...
(unitron) wrote in message . com... (mars) wrote in message . com... The speaker uses an AC adapter, and the label on the ac adapter said it has 12V AC output. I checked the adapter, it had 13.2V AC.And i also checked the two terminals of the switch. it has 17.69DC. Any suggestion? "Michael R. Kesti" wrote in message ... mars wrote: I have a midialnd MLI 480 computer speaker. In a hot day last summer, after i turned the bass and volume almost to full and played game for 30 minute, I turned the speaker off. The next day when i turned on the speaker, it was competely dead. It had no power,led did not light up. So i opened the speaker,I discovered the capacitor next to the amplifier IC was bulged. That capacitor was 16V 4700uF,the largest capacitor on the circuit. I also did the viusal check and tested all of the resistors, diodes and transistors on the circuit using multimeter, every thing was fine. I did not test all of the capacitors since i don't have the oscilloscope The speaker still has no power and no led light after i repalaced the capacitor. I guess the amplifier is the source of problem The amplifier IC is Philips TDA1519A http://www.semiconductors.philips.com/pip/TDA1519A.html Is there any test i can perform to find out the ic is bad? Do i have to replace the IC? Anything else can cause no power for the speaker? Any suggestion! Thanks! The LED not lighting makes me suspect that the power supply is not functioning. I'd test the DC output(s) of the supply before suspecting the amplifier. Do you have the same DC reading across the switch terminals with the switch both on and off? Yes,same reading. Finally, i know why my speaker is dead.Last night, i did a visual check and coutinuity test and i found out a cold solder joint at one pin of the switch(the switch is inside the glued wood case, so it is very tricky to see and test the switch) Anyway, Thank you for all of the help!!! |
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