Please help me fixing my Jvc ax1100,

Guys, I think I found it..
It seems so easy now, but the problem was hiding under a thick cable soldered on the pcb.
A pcb trace had literally exploded..
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I'm going to check now the daughter card connected to the broken trace, but I think this is the culprit. What do you think is the best way to correct it? Can I use a solid core copper cable from an ethernet Lan to connect the pins, or I should solder the pcb trace?
Also what tool do you recommend to unscrew transistors from the heatsink? In the manual they mention a curved screwdriver but I haven't found any small enough to fit the space..

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Also what tool do you recommend to unscrew transistors from the heatsink? In the manual they mention a curved screwdriver but I haven't found any small enough to fit the space..

I generally try a small ratchet fitted with a socket that will then hold a generic screwdriver bit. You don't need much swing room for the ratchet.
 
I noticed that some carbon resistors have shifted their value a lot. For example a 47k is measuring 39k, some even worse, I thought the manual maybe have mistakes, but the color codes of the resistors match with the manual.
Do you guys replace resistors, maybe carbon for metal film, or this is overkill?
 
looks like a spanner will go on the outputs . either that or remove things that are in the way or remove the whole heat-sink assembly with outputs still on .
resistors fail high ohms not low ohms .. i guess you are reading in circuit so will be seeing rest of circuit resistance too ..
 
looks like a spanner will go on the outputs . either that or remove things that are in the way or remove the whole heat-sink assembly with outputs still on .
resistors fail high ohms not low ohms .. i guess you are reading in circuit so will be seeing rest of circuit resistance too ..
Yes I'm reading in circuit, probably they're ok.
 
sometimes if in circuit they make more sense if you swap meter leads over .
did you find what made the track burn up ?
 
The trimpot went open while adjusting iddle current. I think spraying Deoxit on variable resistors is wrong!
4 output transistors were blown, and some fusible resistors, I have checked all other transistors, they seem ok.
The resistors are 1/4w fusible, I noticed that not every store use the name "fusible" or "flameproof"..
I tried to order on Mouser or Digikey, but since I live in Europe (non EU), I have 40$ of shiping for 5 resistors,
Can you recommend any reputable store in Europe, or ebay is ok just for resistors?
 
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Ok, a little update.
After installing everything I turned it on, still protection mode. :whip:
I tried to set the bias but it stays 0. When I was considering to give up, I heard a click, it just got out of protection when I was measuring for the thousandth time the driver transistors. It plays but with a lot of cracks and still too high dc offset..
I desoldered the driver transistors from the pcb. 2 pairs of 2SB649A/2SD669A(Q511,Q512,Q513,Q514), definitely one SB649A is shorted, the other 3 measure ok.

Searching around the web it seems like KSC2690/KSA1220A are good substitutes, I already ordered them, but immediately after buying, I discovered that they are suited for low voltages, I see 60v in the JVC service manual.
I can get the original part from here http://www.bdent.com/nsearch.html?catalog=yhst-864421581610834172249761&query=2sb649
Do you think I should replace all 4?
 
I'm still back to my old amplifier, after checking and rechecking parts, I replaced the driver transistors, and finally it got out of protection.
Everything seems ok, but it stays there nothing plays, when I try to set the iddle current at TP501, it stays 0, for both channels.
I also replaced the trim pots with some Bourn, is it possible that I installed them wrong? The variable resistors are Vr502 in the pic( vr 501 for the other channel),
It seems to be variable resistance between R502 and pin 2 IC502, so it should be ok..
Any idea what can it be? Everything seems ok.
There are some resistors that are measure differently from what is in the manual, but they measure lower resistance, so maybe it's because I'm measuring in the circuit.

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