Ok here is another one...
No visible signs of any fryups or blow outs but when i plug it in it blows the fuse (2a 250v) straight away...
Any ideas?
No visible signs of any fryups or blow outs but when i plug it in it blows the fuse (2a 250v) straight away...
Any ideas?
If it uses the typical output IC (TDA7293?), try unplugging the output module and a new fuse. If it doesn't blow probably bad IC. Of the many that I have worked on that's usually the only thing wrong but sometimes the IC wipes out some parts on the main board also.
Craig
Craig
I have seen a few of these as craig says it is more than likley the output ic.
also check the mute circuit as i have found that when the ic self destructs it takes out a resistor in the mute circuit..
Mad Mark
also check the mute circuit as i have found that when the ic self destructs it takes out a resistor in the mute circuit..
Mad Mark
Those are the parts on the main board I was thinking of, check the zener diode in the mute circuit. The last amp I repaired it was shorted. If it ends up being the output IC you will have two choices, replacing just the IC or replacing the whole module.
Craig
Craig
Hmmmmmmmmmm....
This is doing my head in... am i looking for an obvious burnout? or is it a case of replacing and testing?
All solders and connections on the IC's are fine... ill check the zener diode on the mute circuit when i am back in the studio later tonight but as i said... no obvious burnouts or bad connections...
Poison Pete
This is doing my head in... am i looking for an obvious burnout? or is it a case of replacing and testing?
All solders and connections on the IC's are fine... ill check the zener diode on the mute circuit when i am back in the studio later tonight but as i said... no obvious burnouts or bad connections...
Poison Pete
There may not be anything visible, sometimes they go with flames and sometimes they don't. Unplug the module and power it up.
Craig
Craig
Hmmmmmmmmmm....
This is doing my head in... am i looking for an obvious burnout? or is it a case of replacing and testing?
All solders and connections on the IC's are fine... ill check the zener diode on the mute circuit when i am back in the studio later tonight but as i said... no obvious burnouts or bad connections...
Poison Pete
Even if you did find a burnout there would still be a very good chance other components will have be damaged with no visible sign. Through past experience it will deff be the tda output ic. you may find that when removing the ic a leg will fall off because of damage. order yourself a new tda and fix your amp. Regards Mad Mark
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