Scan, troubleshoot and diagnose automotive and other electrical problems with the STEELMAN PRO 79437 SMM-500 Digital Oscilloscope and Current Meter. Combining the functions of both a 4000 count auto-range True RMS digital multimeter with those of a digital storage oscilloscope, this tool can perform a wide range of diagnostic and analytical tests. The 3.5-inch high contrast LCD display is backlit with 3 brightness settings making it ideal for use in dark areas like engine compartments and underneath automotive dashboards. The tool's DMM functions include True RMS AC/DC current and voltage, resistance, capacitance, frequency, duty cycle, dBm, diode, and continuity tests. Digital storage oscilloscope (DSO) capabilities include trigger mode with auto/normal/single settings, automeasure mode for Vpp, Vavg, Vrms, and dBm, and cursor readout mode for dV, dt, 1/dt(frequency) readings. For ease of use the durable casing has soft-touch function buttons and a built-in kickstand. The meter is powered by a built-in rechargeable Li-ion battery and has an automatic shutoff feature that can be adjusted to engage after 5 to 60 minutes, or alternately, it can be disabled for continuous use. The included AC power adapter allows the meter to operate while plugged in and recharging. A USB interface allows the meter to connect and transmit readings to PCs for further review, sharing, and analysis. DMM AND DSO FUNCTION – Tool combines a 4000 count auto-range True RMS digital multimeter with a digital storage oscilloscope HIGH CONTRAST SCREEN – Readings are displayed on the 3.5-inch FSTN LCD display which features 3 backlight modes for low light use MULTIMETER FUNCTIONS – DMM functions include True RMS AC/DC current and voltage, resistance, capacitance, frequency, duty cycle, dBm, diode, and continuity tests OSCILLOSCOPE FUNCTIONS – DSO functions include auto/normal/single trigger mode, Vpp, Vavg, Vrms, and dBm auto measure and dV, dt, 1/dt cursor readout DURABLE CASING – Rugged casing features soft-touch function buttons and a built-in kickstand LI-ION BATTERY – Comes with a rechargeable lithium-ion battery and AC power adapter for both corded and cordless use PC TRANSFER – Includes a built-in isolated USB/RS232 interface for easy communication of readings to PCs