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Soldering of DSO138 (13803K) DIY Digital Oscilloscope Kit Electronic Learning Kit
MCU is 32-bit ARM Cortex-M3 STM32 F103 at 72 MHz
Features:

Kits using ARM Cortex-M3 processor (STM32F103C8), and includes a 2.4-inch color TFT display can be used as ARM test development board.
Available source, Capable people can be secondary development on the basis of the suite, for example, it can be changed to Millivoltmeter, data loggers, and so on (we don’t supply any technical support about that).
Circuit is simple and the kit is inexpensive

Description:

PCB size: 117 x 76mm
Screen size: 52 x 40mm
Supply voltage: DC 9V

Characteristics of indicators:

Maximum real-time sampling rate: 1Msps
Accuracy: 12Bit
Sampling buffer depth: 1024 bytes
Analog bandwidth: 0 – 200KHz
Vertical Sensitivity: 10mV / Div – 5V / Div (1-2-5 progressive manner)
Adjustable vertical displacement, and with instructions
Input impedance: 1MΩ
Maximum input voltage: 50Vpp (1: 1 probe), 400Vpp (10: 1 probe)
Coupling modes: DC / AC / GND
The horizontal time base range: 10μs / Div – 50s / Div (1-2-5 progressive manner)
With automatic, regular and one-shot mode, easy to capture the moment waveform
Available rising or falling edge trigger
Adjustable trigger level position, and with instructions
Observable previous trigger waveform (negative delay)
Can freeze at any time waveform display (HOLD function)
Comes 1Hz /3.3V square wave test signal source