# Help with LTSpice full-wave rectifier simulation

I'm fairly new to LTSpice and its function. Our professor asked us to construct this specific circuit (in the photo). I tried doing it on my own, but I am not that confident if my LTSpice circuit is the same as the one that is instructed.

Note: Our professor only taught us the basics of LTSpice, like how to put different components etc.

The photo below is my attempt:

May I ask if I should change anything in my LTspice simulation or is it already correct? I also do not know anything about potentiometer or even oscilloscope. Those two terms are fairly new to me.

• I think you should spend some time learning about "oscilloscope" and "potentiometer" before you tackle this assignment. Mar 30, 2021 at 15:51

Your voltages are wrong. 24VAC is the RMS voltage, and LTspice uses peak.

LTspice has a pot component that allows you to set the shaft rotation from 0..1

And you have a short.

Either flip one voltage source or (better IMHO) add a phase shift phi of 180° to one of them).

• It doesn't have a pot, and now I know you might have problems sharing your schematics due to custom libraries not kept in check (or mingled with the default ones from the installation path). :-) Mar 30, 2021 at 18:57
• @aconcernedcitizen Ah, yes. Sharing is not much of a priority for me. Mar 30, 2021 at 19:14

Remove the dot at where the wires cross at the right of X5 - the dot indicates a connection between the wires, and you don't want a connection there.

A potentiometer is a variable resistor. It has three terminals - one for each end of the resistance element, and one for a sliding contact that moves along the resistance element. You have probably used potentiometers as volume controls, light dimmers and many other things that are adjusted by turning a knob.

In a two secondary transformer like yours, the secondary windings are opposite polarity relative to the common, so you get a positive pulse on one, then on the other on the next half cycle.

Flip V2 around 180°.