Hi. I'd like to build a 9 vdc placid-based linear Power Supply. I need max.750 mA current.
I would like to use a toroid transformer dimensioned to maximize efficiency so that the dissipated heat is not big.
Per my experienced, I am tempted to use a transformer with 9v .83 Amps secondary, because I have seen that the voltage increases after smoothing (more than) offsets the lost volts in rectifying and regulating. Would that be too tight?

Thanks in advance.
Jose.