Tommy, a high school student, has shown how it is possible to improve the performance of a low-cost digital storage oscilloscope (DSO) by modifying it to give it greater precision.
The DSO138-mini, which was the focus of the project, has a bandwidth of 100kHz and an effective resolution of 10 bits, but has poor performance due to a lack of effective bits and is often very noisy.
To combat this, Tommy added an anti-aliasing filter to the input to remove high-frequency components that could lower the resolution; and used digital post-processing to remove noise caused by the system’s power supply.
In the second part of the project, Tommy presented experimental data that demonstrated the effectiveness of the changes, with a good percentage of the noise on a test signal removed from the output, at a very low cost.
These modification could also be applied to other low-cost test equipment.
