How would I design a half wave rectified and smoothed power supply that is designed to supply a load with 12 volts, 0.5A, assume the average smooted voltage is 1V below peak value?????
Cheers.

 

http://www.allaboutcircuits.com/vol_3/chpt_3/4.html

This will get you understanding what your asking. And may just answer your question.