Transformers and bridge rectifiers [question]

[The.Pisces]

Why do we use bridge rectifiers with laminated core transformers? If the transformer steps down the voltage to 24v volts (in my case) why should i use a bridge rectifier if i am building a linear voltage regulated power supply.

Currently working on an LM338K linear power supply.

reference:



Another Question Where should I put the other potentiometer to Control the Current

 

[duke37]

The transformer changes 240V AC to 32V AC. In order to get DC it must be rectified which is what the bridge does. The current comes as pulses and these are smoothed by the 3.3mF capacitor.
The LM338 regulates the voltage, it does not regulate the current until it is asked to pass more than its limit.
To regulate the current another LM338 could be placed in front of the voltage regulator, in a different circuit but this will involve some voltage drop so you will not get 37V maximum.

 

[Ratch]

Why do we use bridge rectifiers with laminated core transformers? If the transformer steps down the voltage to 24v volts (in my case) why should i use a bridge rectifier if i am building a linear voltage regulated power supply.

Currently working on an LM338K linear power supply.

reference:



Another Question Where should I put the other potentiometer to Control the Current

Bridge rectifiers make possible full-wave rectification without a center tapped transformer, and only require half the turns ratio. In the above circuit, a two diode full-wave rectifier would require a 64 volt center-tap transformer Laminated cores reduce eddy currents.

Ratch