Toki PCB LA4460N overheats

chinitosoccer

Camel Slug
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Jan 10, 2010
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I have this Toki pcb which plays both video and sound just fine, but the LA4460N in the sound amp section tends to overheat after a few seconds turned on, what can be causing this? should I change the caps?
 

Fox1

Bub & Bob's Bubble Buddy,
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Usually when a amp overheats, the caps have gone bad. Well, that or the amp is bad.
 

chinitosoccer

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Jan 10, 2010
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At first glance I don't see any swollen caps but I will replace them and see if anything changes.

edited: I just remembered that this game requires -5 volts for the sound, perhaps an issue with -5v on the p.supply may be the cause of the overheating..
 
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chinitosoccer

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I replaced the caps marked in red but the amp keeps overheating, and I can barely hear anything, sound is low even with the pot adjusted to the max, do the big caps near the jamma edge are also conected to the sound circuitry? should I replace those too?

 

bustedstr8

Trollbox Trade Federation,
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Oct 15, 2007
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Stick a heatsink on top of it, ground plane cooling doesn't seem to be cutting it.
 

Pasky

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Check for shorts first. Could be causing it to overheat.
 

chinitosoccer

Camel Slug
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Jan 10, 2010
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Installing a heatsink was my first thought, looking for shorts was one of the first things I did, but either I couldn't find it or there isn't any.

One thing I noticed is that the thing doesn't get that hot if I left the speakers on my cabs/supergun unplugged.
 
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