DSO138 was designed as a training oscilloscope kit. Simplicity in structure and easiness in assembly/operation are the main targets of its design. For these purposes, DSO138 applies mostly through-hole parts and the heart of DSO138 is a Cortex-M3 ARM processor (STM32F103C8) from ST. It also uses 2.4-inch TFT LCD (320 X 240 dotmatrix, 262K colors) as its display element that will display nice clear waveforms. Detailed assembly instructions are provided in combination with troubleshooting guide and schematic. This DSO138 kit has all SMD parts pre-soldered. The MCU has been pre-programmed and no re-programming required.