dual rail from a 3 wire transformer?

Hi Everyone

How can I get a dual rail supply from a transformer like this?

The output DC voltage has to be higher than 14 volts.

Thanks.

A bridge rectifier wired as two full wave rectifiers with two smoothing caps will give about +17/-17V DC, it's a perfectly standard circuit.

hannobisschoff@gmail.com said:

Hi Everyone

How can I get a dual rail supply from a transformer like this?View attachment 60151

The output DC voltage has to be higher than 14 volts.

Thanks.

Click to expand...

Straight forwards...secondary tap is ac +/- 12 volts with a 0 volt rail (this will be your earth/o voltage..... so moving on, select a dioderectifier unit and a pair of capacitors say 2000uf at 35vdc next wire the caps for dual supply like so.. each 12v ac tap is linked to bridgeunit ac input and the following connections will be + dc /-dc these are fed to the filter caps... look at any dual rail supply circuit on line and your see how the caps connections are wired together as a zero volt common. the above psu would give a unloaded supply of just over 15+/- volts.

Configure the transformer per the attached and chop the circuit off prior to the regulators. Just a cartoon of what everyone has said.

Ron

Having never made a dual rail PS, my first thought was that one would need two bridge rectifiers. I learned something new, and on a Saturday.

Thanks a lot guys, I'll follow the above schematic.

my first thought was that one would need two bridge rectifiers

Click to expand...

You could if you what to use smaller caps.