It looks like most people on the forums have trouble with aluminum electrolytics, but I have an old oscilloscope with a shorted tantalum in the power supply. At least I think its a tantalum. It is cylindrical shaped, axial leaded, with one end rounded to indicate polarity. 4.7uF, 50V, Kemet. The cap is shorted and burned through.
The power supply is a conventional linear design. Transformer, rectifier, filter caps and linear regulators. The shorted capacitor was on the input side of a LM337 regulator and took out a bridge rectifier, but not the fuse.
I was wondering if anyone has experiance replacing tantalums that failed in this way? Should I replace it with a tantalum? I've read that they can fail from current surges. I've had other equipment with tantalum filter caps that failed in the same way (bang! smoke...). Should I look at replacing the tantalums with aluminum electrolytics or some other type? Also, I counted 12 tantalum capacitors on this power supply board. I guess the good ones could fail at anytime. Should I recap the whole power supply? But recapping could be expensive, a 10V, 220 uF, axial tantalum is listed at $12.28 on digikey.
Thanks for any help.
The power supply is a conventional linear design. Transformer, rectifier, filter caps and linear regulators. The shorted capacitor was on the input side of a LM337 regulator and took out a bridge rectifier, but not the fuse.
I was wondering if anyone has experiance replacing tantalums that failed in this way? Should I replace it with a tantalum? I've read that they can fail from current surges. I've had other equipment with tantalum filter caps that failed in the same way (bang! smoke...). Should I look at replacing the tantalums with aluminum electrolytics or some other type? Also, I counted 12 tantalum capacitors on this power supply board. I guess the good ones could fail at anytime. Should I recap the whole power supply? But recapping could be expensive, a 10V, 220 uF, axial tantalum is listed at $12.28 on digikey.
Thanks for any help.
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