Week 5

The report of working process in the last week
After modification of the past circuits, our group has changed many times of the whole circuit structure.

The oscilloscopes in the lab includes 3 types. One is newer and the other 2 are older types. However, the output waveform only appeared in the one type in old fashioned series, which can be easily zero set by us. ( The teaching assists also said they were not similar to the latest models of oscilloscope so we chose the simpler ones.) When we were applying the simulated sine-solid inputs the outputs can be considered to be reasonable. However, the magnifications are not same as we calculated. Then we changed the values of resistances and moved the capacitors many times to improve the results. In these process we found lot of mistakes. One traditional sample is we forgot to let the resistor which was connected to the source pin to ground. When we started to apply the RE200b into the circuits to test the latest circuit more problems occurred.

The output waveform turned to be abnormal. When we tried to remove some capacitors it can be better but also far away from the expected result. Then we changed to amplifier LM1458 into Lm324. But this time we still failed and cannot find the core of the problems. Then the time limit in the lab came. Our group had no more time to finish this task. It might be a pity for there process because no appropriate achievement was created although the simulation work is good.