The JHJDS2012S is a handheld electrical test device that combines a 25 MHz, single-channel, handheld digital oscilloscope for viewing electrical signals with a manual- and auto-ranging digital multimeter for measuring AC voltage to 750V and DC voltage to 1000V,resistance to 40 MΩ, and capacitance to 4000 μF. The oscilloscope has maximum real-time sample rate of 200MSa/s and a record length of 4,000 points for acquiring detailed waveforms. Its 18 automatic measurements such as period, frequency, and peak-to-peak enable an in-depth analysis of waveforms. Up to 6 waveforms can be stored in the internal memory. The multimeter has two ranging modes: manual, which allows the user to select the operating range, and auto, which automatically selects the appropriate operating range. The delta relative function allows a measurement to be set as a reference value and displays subsequent measurements as a positive or negative deviation from that value, and the data-hold function freezes a reading on the display to aid documentation. A continuity buzzer confirms that the circuit conducts electricity, and a diode check detects whether a circuit's diodes are working properly. Additional specifications include various triggering features. The unit has a 3.5" color TFT (thin film transistor) LCD with a resolution of 320 x 240 pixels for viewing waveforms and measurements. An oscilloscope is used for electronics applications such as product design, assembly lines, repair and servicing, and electrical engineering education, among others. A multimeter is an electrical testing tool for measuring multiple properties of an electrical circuit to verify proper operation or diagnose problems. The unit has a USB port for connecting to a PC, It is rated for CAT II installations to 400V, which covers energy-consuming equipment connected to a fixed installation, including household, office, and laboratory. It has European Conformity (CE) marking.