DSO138 was designed as a training oscilloscope kit. It contains only the basical oscilloscope functions with no fancy features.
Simplicity in structure and easiness in assembly/operation are among the main targets of the design. For these purpose DSO138 uses mostly through-hole parts.
The heart of DSO138 is a Cortex-M3 ARM processor (STM32F103C8) from ST. Its 2.4-inch TFT LCD (320 x 240 dotmatrix, 262K colors) displays nice and clear waveforms.
Detailed assembly instructions are provided in combination with troubleshooting guide and schematc. Source codes are also available to allow user to add their own features.
DSO138 is partially open-sourced. This opens the possibility for users to add different features or develop new applications on the hardware.
Am new to mine, but am amazed at its functionality and list of features. A REAL good way to learn about O-scopes without dumping a ton of money into my first scope (OK, my first was an ancient, defective analog scope that didn't work much, and taught me nearly nothing. Be sure to read up some on O-scopes before using, and only use low-voltage connections (under 30V) -- not for checking AC house line current unless thru a 10X probe; definitely not for HIGH voltages. Also only good for audio frequencies and below (maybe a bit of ultrasound up to 40-50kHz or so), but that's where you should begin learning Oscope work anyway, IMHO. LOTS of features, more than I'd expect. Take TIME to learn the awkward menu and controls; you'll be nicely rewarded with a TON of useful features. Very awkward to use without a case, but some are for sale online, and so are plans for 3D printers to print one. You'll outgrow it soon, but it's a GREAT starting place, and you'll find it useful for years (if it lasts).