Umm . . . The 470 vs 220 uF on the -15, +15 supplies are almost always due to differing current demands -- the negative rail is more heavily loaded, even if only occasionally.
Different capacitor materials and constructions do behave differently over frequency, of course, but I don't think that's a factor in this instance. 78xx and 79xx parts are pretty sturdy.
Also, when Extreme_Boky was talking about 100 uF at regulator inputs, I think (s)he meant at local sub-regs. A centrally located main supply certainly needs more, just to keep up the voltage between current pulses from the bridge, which only come along every 8.3 or 10 milliseconds.
Regards,
Rick
Different capacitor materials and constructions do behave differently over frequency, of course, but I don't think that's a factor in this instance. 78xx and 79xx parts are pretty sturdy.
Also, when Extreme_Boky was talking about 100 uF at regulator inputs, I think (s)he meant at local sub-regs. A centrally located main supply certainly needs more, just to keep up the voltage between current pulses from the bridge, which only come along every 8.3 or 10 milliseconds.
Regards,
Rick