Re: Philips BX281U20 valve radio
Like Marten, i was surprised by a ripple current of nearly a whole amp in such a small space. This is a live chassis set and so has a half wave rectifier, the capacitor has to work twice as hard as full wave - its a configuration that works the component very hard (the data sheets don't quote below 50 hz!) , so i had a quick check on the datasheet i used last time i bought bits. Of course it is unlikely to be for the same component -or even the same maker as yours, but the ballpark numbers may make a second check worthwhile.
For 250V it gave 930mA for a 220mFd
and 330mA for a 47mFd.
These were at 120Hz, so would reduce to 230 mA at 50 Hz for a 47mFd.
There is a formula to work out ripple current which i can't remember, but which will be unnecessary if the spec of your capacitor is 920mA.
But it's an easy table to miss-read, and 920mA is very close to 930mA (which is why i mention this) and a quick re-check now may save difficulty later.
As Marten says, you can expect a half wave configuration like this to impose a significant ripple, and associated stress!
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