[sdiy] electrolitics for pcb power input

[Fernando de Izuzquiza]

Hi,

I may buy some electrolitics in large quantity to get them chaper and  
I'd like to know about the criteria to choose them.

These will be used at the power input on each circuit board.
I see some people use 10uF, some other 100uF.
Some at 25V, others 35V or 50V.
(I'll be using +-15V PSUs)

Also, worth to get them of the Panasonic types? Long life is  
important for me.

And, wich other values are the most common for circuit usage (I know  
Harry preffers non-polars for that!)
4.7uF? 47uF?

Thanks,

Fernando