? Carefully design (using hand calculations), and simulate each stage of the circuit, and the
circuit overall. If your simulation and design don’t match, don’t proceed until you understand
why!! Make sure you know what to expect when you construct the circuit!
? When you construct your circuit on breadboard, ensure it is neat and tidy. Use colour coded
hook-up wire, trim wire and component legs so components are flat on the board:
o Easy to check circuit
o Minimise noise, resistance and reactance from “loopy” wires acting as antennas
o More robust to movement (i.e. won’t accidently knock out a wire during a
demonstration).
? Check the pin-outs in datasheet for each component. Check coding’s on each component to
ensure it is what you think it is…..If possible, measure each component to check (i.e. resistors,
transistor beta values)
? Carefully construct the first stage of the circuit. Design an appropriate
experiment/measurements to ensure it works as expected.
? Carefully construct the next stage of the circuit in isolation. Verify this stage works as
expected in isolation.
? When both stages work independently, connect the output of the first stage, to the input of the
second stage, and verify that this circuit works as expected.
? Construct the next stage, verify it works in isolation, then connect to the output of the previous
stage to check that the entire circuit so far works as expected.
? Repeat for each stage of the circuit until you reach the end.
? If at any stage the constructed circuit does not work as expected, stop and work out why.
Because you are working in stages, the problem will be constrained to a relatively small
number of components, and this should be easy to work out.
o Use appropriate measurements to work out what the circuit IS doing. This will often
give you a clue as to what is the source of error. In the case of discrete transistors: