hello.
I have an alpine 9870 and yesterday from my player i saw smoke. Today i have opened the chaisis i have found the ground shield broke. I have replaced with a wire the ground shield and again it smell burned. I came back home and i have put 2 wires on each ground wire from the board that are connected to the power ic and the rca ground.
Now the player works fine, because when the shield blows, the ground circuit opens and the power ic from the player doesn't have ground and it results no music in my speakers.
I have and hifonics bx1500D with 2 polk audio subwofers briged at 2 ohms(1000W). I measured and at the rca of the amp the multimeter don't indicates continuos with the ground(the exterior of the rca and the ground of the amp). But the amp has imput and an output pair of rca. The exerior of these two pairs of input and output are conected toghether but they aren't connected to the ground.
Now i leave the rca fom the player in the air, i mean not connected to the amp and the player works perfectly. I don't want to connect again because the ground shield from the plyer probably with blow again.
I measure if it exists any conctact with 12V on the rca cable and the result was negative.
Could you give me a cause why the rca of the amp is not connected to the ground? It is normal? I will protect the circuit with a fuse because i don't want to repair third time the ground shield. What can be the value of the fuse in this case?
P.S. i want to say that my amp enters in protection mode when i set from my player to much volume.
Sorry for my english!
I have an alpine 9870 and yesterday from my player i saw smoke. Today i have opened the chaisis i have found the ground shield broke. I have replaced with a wire the ground shield and again it smell burned. I came back home and i have put 2 wires on each ground wire from the board that are connected to the power ic and the rca ground.
Now the player works fine, because when the shield blows, the ground circuit opens and the power ic from the player doesn't have ground and it results no music in my speakers.
I have and hifonics bx1500D with 2 polk audio subwofers briged at 2 ohms(1000W). I measured and at the rca of the amp the multimeter don't indicates continuos with the ground(the exterior of the rca and the ground of the amp). But the amp has imput and an output pair of rca. The exerior of these two pairs of input and output are conected toghether but they aren't connected to the ground.
Now i leave the rca fom the player in the air, i mean not connected to the amp and the player works perfectly. I don't want to connect again because the ground shield from the plyer probably with blow again.
I measure if it exists any conctact with 12V on the rca cable and the result was negative.
Could you give me a cause why the rca of the amp is not connected to the ground? It is normal? I will protect the circuit with a fuse because i don't want to repair third time the ground shield. What can be the value of the fuse in this case?
P.S. i want to say that my amp enters in protection mode when i set from my player to much volume.
Sorry for my english!
This is common when the transformer shorts between windings. The short is often intermittent which means that you may not initially find voltage on the RCA shields of the amp. Remove the cover from the amp. Place the black probe on the amplifier's ground terminal. Place the red probe on the input RCA shield. Twist/push/pull on the transformers. Does the voltage ever go from well under 1v to near 12v?
Do this with power applied to the amp but no remote voltage. Don't connect the RCAs from the head unit to the amp.
Do this with power applied to the amp but no remote voltage. Don't connect the RCAs from the head unit to the amp.
the transformer from the power suplly or the transformer from the amp part. i put a photo with the amp. Could you indicate in this photo what is the transformer that you talk about. Please!
Do you mean to measure betwen the ground of the amp and the "ground" of the rca, or on the positive part of the rca connectors?
The photo is old when i replaced the transistors from the power suplly
Do you mean to measure betwen the ground of the amp and the "ground" of the rca, or on the positive part of the rca connectors?
The photo is old when i replaced the transistors from the power suplly
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you're right! if i twist one of the transformer between ground and the negative of the rca i found 12V. What is the solution?
Do you know how thick is the wire from each transformer? i need to repair them, but i don't know how... i know that i need to use Cu-Embut in the rest i don't know...
Can you help me with informations?
can i use one wire instead of 5 wires, it will be much more thick.
Do you know how thick is the wire from each transformer? i need to repair them, but i don't know how... i know that i need to use Cu-Embut in the rest i don't know...
Can you help me with informations?
can i use one wire instead of 5 wires, it will be much more thick.
Don't try to rewind the transformer unless you absolutely have to.
The most common place for the transformer to short is the point where the terminal windings (the ones that solder to the board) make contact with the rest of the windings. For the transformer that's shorted, pull those windings away from the rest of the windings. Does that prevent the prevent the transformer from shorting when you twist it?
The most common place for the transformer to short is the point where the terminal windings (the ones that solder to the board) make contact with the rest of the windings. For the transformer that's shorted, pull those windings away from the rest of the windings. Does that prevent the prevent the transformer from shorting when you twist it?
the distance between the holes where the wires goes into the pcb is big. i discovered a couple of places where the transfomers is shorted. to many places to put some glue to repair the damage. If i proceed and i respect what you said it means to desolder the wires and to put a insolating material betwen the layers.
i hurry up and now i will try to repair. it is hard but i don't think when i decided to rewind.
i hurry up and now i will try to repair. it is hard but i don't think when i decided to rewind.
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