It should be that the voltage value of pulsating DC after rectification bridge shaping is lower than that before rectification!

This is because the diode in the rectifier bridge has a forward voltage drop!

The theoretical value of forward voltage drop of a single silicon diode is 0.7V! But the actual forward pressure drop on the line is 1-2V!

Half-wave of bridge rectifier flows through two diodes! Therefore, the peak of DC ripple is lower than the original AC peak!

The voltage value of pulsating DC after rectification bridge shaping is higher than that before rectification!

This should be a rectifier circuit with a filter capacitor!

Because the capacitor has the function of energy storage! Its terminal voltage can be charged to the peak of the circuit voltage! This peak is 1.4 14 times the average!