WOC2K is a simple digital two-channels oscilloscope module for PC computer. Its characteristic features are very good parameters in relation to its price, clear interface of the user and not very complicated construction with the application of cheap and popular electronic components. The heart of the oscilloscope is 32 bits microcontroller ARM LPC2142 equipped with internal memory RAM, program memory Flash, ports I/O and serial port UART. The controller is clocking by internal generator with PLL synthesis which enables to get 18MS/s sampling on the channel. The analog tracks of A and B channels, as well as AD AD9280 converters are independent from each other. This allows to receive a good inter channels separation min 60dB. The increase in the system functionality was possible by applying differential inputs. For the communication of the system with the computer the integrated system of USB-RS232 FT232R bridge was used, where on the side of serial port the device was optically separated from PC and FTDI interface. Thanks to the application of small converter separating DC-DC 5V and bistable relays the external power supply of the add-on device was given up. The whole device is in 120x90 mm case and it is supplied directly from USB port. In front of the case there are BNC connectors and LED transmission indicator. Not only xOC2K application enables almost all function which provide analog oscilloscope, but also many others. For instance: FFT analysis, FIR filtering, trace mode A,B, mathematic function (sum course, multiply course, inverse etc.), cursors, measurements, print, load and save. rOC4K software allows to record long courses (limit by size of hard disk) at 10kHz maximum sampling. Additionally, recorder can calculate FFT on arbitrarily long date, but the window of data is limited to 65536 samples and result is the average of this windows. Developed oscilloscope is destined to amateurs electronic, services, schools and universities, telecommunication companies and automotive. WOC2K is a perfect tool for audio devices and microprocessor systems.