The Advance OS250 Oscilloscope is a 10 MHz dual trace instrument with a 10cm x 8cm display. It is designed for use in general purpose laboratory work, educational uses, TV and servicing applications. It features two identical input channels with a maximum sensitivity of 5mV/cm and a bandwidth of DC to 10MHz. The two channels may be viewed separately, alternately at fast timebase speeds, or chopped at a 250kHz rate at low timebase speeds. Particular attention has been paid to trigger performance, and the system used includes a variable control with bright line operation in the absence of a signal, or when the trigger level is outside the range of the input signal.