In this month of foolish April, I bring you one of my worst moment in interviewing about the assignment which was just concluded. Why?
The moment when I walked into the room, I met Mr. Chan after my other groups have been interviewed by him for individual assessment. He smiles at me, and the assessment is stated immediately without wasting time.
This is my own Q&A session for my interview-cum-presentation moment:
Chan: *Looking through the report and asked* "Are you in charge of the summing circuit?"
Chan: "Ok. So I want to know how did you find out the gain of the summing circuit when one of the input is being injected."
sonnykazu: Emm... The gain is calculated by using the formula, (bla bla bla) so the gain is unity gain 1. When I combine the two inputs together, they will sum up to become 2 at the output."
Chan: "Ok. (*He showed me about the formula that is written in the report. I quickly noticed that the calculation for gain is wrong, which is supposed to be -2. I was getting more panic." Why did you use TL071 op-amp instead of LM741 or TL082? What's so special about it?"
sonnykazu: *I paused for almost a minute. I can't think anymore but I still say out...* "Well, TL071 is a single op-amp, which is price of the component is almost the same as the LM741."
Chan: "Actually TL071 is similar to LM741 which has a single op-amp, but what is special for you by choosing TL071 as your preferred component. No special reason?"
sonnykazu: *Paused for a moment...* "I guess no..."
Chan: Ok. So show me how you get the results shown in your report.
sonnykazu: *I was then troubleshoot the circuit to get the same output as the report. However, I noticed that the output shown at that time is totally different than the report shown. OMG! I was shocked... and I'm helpless.* "Sir, the report shows the inverting output as we have tested in the project lab, but why I get this non-inverting output? That doesn't make any sense." *I am sure that I have connected the circuit correctly. No mistakes I swear!*
Chan: "Hmm... I don't know. What you have showed me now is not that same as the report shown. Probably there are many factors which causes the circuit to be differ from what you have get before that. Just like when you carry the circuit board around, the components might be loosen. Another possibility is that the temperature might effect the circuit." *I agree. His statement is reasonable.* So that's all... thank you!
He showed me my individual results, and I am quite unhappy for myself. I'm gonna repay my marks for doing assignment 3, which is to transfer the whole circuit to veroboard. Now it's my turn to help the group. I am worried about my final marks, I have a slight chance to pass the subject. I need more understanding about electronic circuits! Please help me...!
Don't forget, Happy April's Fool!!! xD