Greeting Folks,
I recently purchased a nonfunctional Orange Crush 20RT chasis and found a charred resistor in the power supply rail during inspection of the pcb. The resistor is connected to the -15V rail generated by a 7915 regulator and was found to be open circuit when tested. Surprisingly, the voltage on the downstream leg of the resistance was found to be +14.5V when the amp was powered up. Following the associated pcb trace with this leg brings us to a component labeled C40, which I assume is a capacitor. The other end of C40 is connected to the +15V supply rail for the NE5532 op amp.
Measuring the resistance across C40 using my fluke multimeter shows a value of 160 ohms. There's a similar component elsewhere on the board but its resistance was found to be much higher, which leads me to believe C40 component may be damaged and essentially shorted the +15V and -15V power supply rails resulting in the fried resistor, R88. The other possibility is that the NE5532 opamp is damaged as it is in parallel to C40.
I would like to start by replacing C40 along with the fried resistor but cannot identify the type of device. Could somebody please help me identify device c40. Pictures of the area are attached,
BTW, I wasn't able to find any schematics for this amp despite an extensive search, and can post high resolution pictures in case somebody is interested.
Many Thanks for your help!
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I recently purchased a nonfunctional Orange Crush 20RT chasis and found a charred resistor in the power supply rail during inspection of the pcb. The resistor is connected to the -15V rail generated by a 7915 regulator and was found to be open circuit when tested. Surprisingly, the voltage on the downstream leg of the resistance was found to be +14.5V when the amp was powered up. Following the associated pcb trace with this leg brings us to a component labeled C40, which I assume is a capacitor. The other end of C40 is connected to the +15V supply rail for the NE5532 op amp.
Measuring the resistance across C40 using my fluke multimeter shows a value of 160 ohms. There's a similar component elsewhere on the board but its resistance was found to be much higher, which leads me to believe C40 component may be damaged and essentially shorted the +15V and -15V power supply rails resulting in the fried resistor, R88. The other possibility is that the NE5532 opamp is damaged as it is in parallel to C40.
I would like to start by replacing C40 along with the fried resistor but cannot identify the type of device. Could somebody please help me identify device c40. Pictures of the area are attached,
BTW, I wasn't able to find any schematics for this amp despite an extensive search, and can post high resolution pictures in case somebody is interested.
Many Thanks for your help!
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