Re: The Hall of Shame - Badcaps Photo Montage
That's a classic transformer, which means the other components are just a bridge rectifier and the capacitor to smooth out the output.
7.5v and 900 mA makes it a 10-15 VA transformer, and with those low VA values, it's common to have up to 20% variation in output voltage when there's no load.
The transformer is also selected in such a way as to have higher output AC voltage, to account for losses in the bridge rectifier and to make it possible to use smaller capacitors.
This, coupled with small voltage drop on diodes at low currents (when you don't have anything connected to it) makes 10v quite reasonable. As soon as you have something connected to it, the voltage will drop.
As you're dealing with 100-120 Hz, general purpose capacitors would work fine. You're not dealing with 30-150kHz frequencies common with switching power supplies. to require low esr capacitors.
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So basically any general purpose capacitor is fine there. It may have been damaged in factory, but doesn't matter, eventually they die... it's a closed enclosure, no ventilation, and classic transformers heat up when in use.
That's a classic transformer, which means the other components are just a bridge rectifier and the capacitor to smooth out the output.
7.5v and 900 mA makes it a 10-15 VA transformer, and with those low VA values, it's common to have up to 20% variation in output voltage when there's no load.
The transformer is also selected in such a way as to have higher output AC voltage, to account for losses in the bridge rectifier and to make it possible to use smaller capacitors.
This, coupled with small voltage drop on diodes at low currents (when you don't have anything connected to it) makes 10v quite reasonable. As soon as you have something connected to it, the voltage will drop.
As you're dealing with 100-120 Hz, general purpose capacitors would work fine. You're not dealing with 30-150kHz frequencies common with switching power supplies. to require low esr capacitors.
-
So basically any general purpose capacitor is fine there. It may have been damaged in factory, but doesn't matter, eventually they die... it's a closed enclosure, no ventilation, and classic transformers heat up when in use.
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