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Home amp fuse bown always

Ferdz

Jan 27, 2018
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hi my home amp fuse always blown up how to identify the cause of fuse blown plss help me my amp is av-502A


2018-01-27-14-06-02-jpg.38960
 
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dave9

Mar 5, 2017
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A common cause of that in audio amps is blown output transistor(s), but could be something else. Is there any chance you can find a schematic or post good high-res pictures of the circuit board? Also look around the circuit board for evidence of overheating, or domed/vented capacitors.

I found what might be the schematic for it but don't have a chance to look at it right now, maybe someone else can make use of it.
 

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Ferdz

Jan 27, 2018
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I check the capacitors ang transistor but they are okay
si what is the possible problem
 

Ferdz

Jan 27, 2018
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Jan 27, 2018
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I check the capasitor and the transistor they are both ok
 

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duke37

Jan 9, 2011
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If you have replaced a NPN transistor for a PNP and vice versa then they could be toast.
To get some volts in without blowing the main fuse, then use a series lamp of about 40W in the mains lead. Then see if any components get warm.
I cannot read the circuit diagram easily but if there is a fuse for each channel, find the channel which is giving the short. I would start with the power rectifier and move forward through the circuit. You may need to cut the traces at critical points to do this.
Have you checked the bridge rectifier, check for diode shorts in circuit and confirm by removal if suspect?
 
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