2nd Lab

We came up with our first designed circuit shown as below, and the simulation of the circuit was correct. (Detailed designing processes are in another post named "Our complete designing processes of this project".)

The first draft of our design

We tried to build the circuit on the breadboard. After we built the circuit, we tried to power the circuit and display the output voltage on the oscilloscope  But the output voltage was always zero and could not be adjusted when we tried to change the resistance of the potentiometer. The supervisor told us that there existed some problem in our design. In his opinion, the whole circuit works like a potentiometer rather than a power supply. He suggest we add a 50 ohms load to the output ports and try to power it. If we can manege to generate a current of several amperes through it, then the circuit is approximately successful.

We tried to simulate the circuit using PSpice. However, PSpice is not advanced enough and it lacks of some essential components that the circuit needs. Simulation failed.

We tried another soft ware called LTspice which was recommended by the supervisor. But there was some problem with the input transformer, the circuit cannot be simulated.

The demonstrator came and tried to fix the problem. But she cannot find out the problem in the circuit either.

We searched Internet to learn about how to use LTspice, because it is a brand new software for us who come from XJTLU. It took us the rest of the lab day.