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Help with dual regulated power supply circuit

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xitian

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I need a little help building a dual regulated power supply that will output 5vDC and 12vDC. Please let me know if you see any problems with my circuit or a way to do it better as I am pretty new at this. Attached is a diagram.

Thanks!
 

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Well, I've never seen such symbols for voltage regulators but
that's ok. Your schematic will not work because capacitor is
wired wrong. It should be accross bridge rectifier output.
It also should be 10-20 times bigger. Other than that everyhing is ok.
You could cascade regulators. This is specially prefered if
current draw on 12V is low but on 5V is high.
Some regulators really should have diode accross regulators input
and output to protect them. I guess it doesn't hurt to put them
anywhere.
Following should give you an idea.
 

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Thanks for the info!

panic mode said:
Following should give you an idea.

Thanks..I have a few questions for you:

1.) How is the capacitor wired wrong? Do I have the polarity reversed? The arrow on a capacitor like in this project always points to (-) right?

2.) Do you know of a formula or website I can use to determine how big of a capacitor I will need?

3.) What do the lines with the two horizonal small lines between the main (+) and the (-) mean? Are they just indicators for the ground?
 
The capacitor should come across rectifier's (+) output and ground. The I inputs of regulators should be directly fed from rectifiers output.
See modified schematic below.
 

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