HELP with w440a montarbo

[tiesto23]

hi i buy this montarbo w440a

when i check there is no power i open the back of the speaker and check board

i find many burned component i want to know their ref


those are photo

[J M Fahey]

hi i buy this montarbo w440a

when i check there is no power i open the back of the speaker and check board

i find many burned component i want to know their ref


those are photo

[ATTACH=CONFIG]51427[/ATTACH][ATTACH=CONFIG]51428[/ATTACH]

Schematic:

[tiesto23]

Schematic:

can you help me identify this exact part on the schematic

the borad i have is damaged






thnx

[The Dude]

That's going to be a quite extensive repair. You've got several burnt resistors, which means something shorted. Aside from that, there's the burnt board and all the burnt traces to clean up and rebuild. Then, you'll have to find the root cause or shorted device(s). If you're not an experienced tech, I wouldn't event try it. You'll have to trace out everything on the schematic since they didn't see fit to silk screen the board with designation numbers. You're probably better off getting new board(s) or a new amp module. It's probably cheaper to just replace even for an experienced tech- lots of time and parts.

[tiesto23]

That's going to be a quite extensive repair. You've got several burnt resistors, which means something shorted. Aside from that, there's the burnt board and all the burnt traces to clean up and rebuild. Then, you'll have to find the root cause or shorted device(s). If you're not an experienced tech, I wouldn't event try it. You'll have to trace out everything on the schematic since they didn't see fit to silk screen the board with designation numbers. You're probably better off getting new board(s) or a new amp module. It's probably cheaper to just replace even for an experienced tech- lots of time and parts.

from my side its not problem of money or time i want to fix it

[g1]

Can you read schematics? If not, I don't think you will be able to fix it. You are going to have to trace out the schematic connections to fix and verify the burnt traces. It's not something that can be done without the unit, so no one here can tell you what to do without access to the burnt board.
If you can read schematics, the board is the one called 440F on the schematic. It is 2 circuits that are mirror images (high and low), plus the 15V +&- supplies. So you can look at the good side to find the value of the bad side.
Aside from the parts you circled, there is a cap bulging and ready to burst by the ribbon connector. Also, on the other board you had a picture of, there is a burnt resistor. So, if you fix this board, the other board may be bad also. And if the amps are bad, the speakers could be blown too.
So check the speakers before anything.

[tiesto23]

Can you read schematics? If not, I don't think you will be able to fix it. You are going to have to trace out the schematic connections to fix and verify the burnt traces. It's not something that can be done without the unit, so no one here can tell you what to do without access to the burnt board.
If you can read schematics, the board is the one called 440F on the schematic. It is 2 circuits that are mirror images (high and low), plus the 15V +&- supplies. So you can look at the good side to find the value of the bad side.
Aside from the parts you circled, there is a cap bulging and ready to burst by the ribbon connector. Also, on the other board you had a picture of, there is a burnt resistor. So, if you fix this board, the other board may be bad also. And if the amps are bad, the speakers could be blown too.
So check the speakers before anything.

i check the speaker and working good with other externel amp

i identify some part

but the problem is on burned sport totaly blind sport for me

i hope someone have same speaker as i have so it will be very easy

i found picture on the web same ( not fully detailed) as my amp so it help me to identify some component

[g1]

These pictures?
http://jestineyong.com/must-read-ita...-improvements/

[nosaj]

These pictures?
http://jestineyong.com/must-read-ita...-improvements/

Maybe same amp but not same pictures of the same section.

nosaj

[tiesto23]

These pictures?
http://jestineyong.com/must-read-ita...-improvements/

yes those picutre are same as my speacker system

[tiesto23]

Maybe same amp but not same pictures of the same section.

nosaj

this is same section

of my burned board





compare the picture

[Enzo]

Upper right just outside the red circle is an MJE15032 transistor. It is almost certainly dead. Chances are the other similar transistors may be dead.

Identify and replace at least the five small transistors in the circle. Four are in sight, the fifth went to the three solder pads near the top of the ring. Across the center of the ring, the two diodes on the right look like common types. The two resistors next to them appear to be 47 ohms. The two resistors on the left appear to be 22 ohm. Resistor next to the missing transistor, maybe 100 ohms?

Top of the picture just outside the ring, a burnt resistor between the orange cap and the heat sink transistor. No idea. Upper left corner of board, a lonesome transistor, looks shaky to me. Frosty solder.

All that damage pretty much guarantees that the heat sink transistors are damaged. And that in turn tells me the power transistors on the other board are damaged.

This will not be easy even for an experienced professional.

[tiesto23]

Upper right just outside the red circle is an MJE15032 transistor. It is almost certainly dead. Chances are the other similar transistors may be dead.

Identify and replace at least the five small transistors in the circle. Four are in sight, the fifth went to the three solder pads near the top of the ring. Across the center of the ring, the two diodes on the right look like common types. The two resistors next to them appear to be 47 ohms. The two resistors on the left appear to be 22 ohm. Resistor next to the missing transistor, maybe 100 ohms?

Top of the picture just outside the ring, a burnt resistor between the orange cap and the heat sink transistor. No idea. Upper left corner of board, a lonesome transistor, looks shaky to me. Frosty solder.

All that damage pretty much guarantees that the heat sink transistors are damaged. And that in turn tells me the power transistors on the other board are damaged.

This will not be easy even for an experienced professional.

thnx alot

mostly the part that you identify same as my identification

for the MJE15032 there is trace of new solder i think it was changed recently ( but i will whange then all and install custom heatsink)

yes right there is 2 power transistor without leg ( totaly burned)

i think WWII was made on this amp ...

[g1]

What is your level of experience for repairs tiesto23 ?
It will help us with our responses to know if you are a technician or hobbyist.

[tiesto23]

What is your level of experience for repairs tiesto23 ?
It will help us with our responses to know if you are a technician or hobbyist.

you can say both technicien and hobbyist

you can say 5/10 mostly i m technicien of pc& laptops

but asmy hobby is playing music and do some repair on instrument or iteam that i buy for myself