INTRODUCTION The PM 3311 Digital Storage Oscilloscope is a portable, two-channel 60 MHz measuring instrument featuring micro-processor controlled electronic circuits. A compact ergonomic design facilitates the extensive measuring capabilities of the instrument. The versatile circuit arrangement combined with the software of the micro-processor gives a wide range of facilities, including: — Brilliant display. — Pre-trigger view. — Storage of two channels with four different "event" signals per channel. — IEC-bus optional (with the aid of PM 3325). — Plotter output. — Trigger delay. — Battery powered memory back-up. Furthermore, a large 8 cm x 10 cm screen with illuminated graticule lines provides for easier viewing, a 10 kV accelerating potential giving a high-intensity trace with a well-defined spot. The oscilloscope is provided with numerous integrated circuits, which ensure stable operation and reducethe number of adjusting points. The supply voltage can be set to one of two ranges: 100 ... 120 V ± 10 % or 220 ... 240 V ± 10 %. As a result of the features listed above, the oscilloscope is suitable for a wide range of applications, for example the measurement and observation of: — Rise-time (gives brilliant display intensity). — Fast signals with a very low repetition rate. — Very low frequency signals (up to 1 hour per division).