The PM2535 is a digital, automatic multimeter controlled by a microcomputer. The instrument has the following capabilities: - Standard multimeter functions - Help functions - Input of figures - Extended capabilities via the IEC-625/IEEE-488 interface The standard multimeter functions (white text) are: - Direct voltages - Alternating voltages (V~) true RMS, ac coupled. - Direct currents (A—) - Alternating currents (A~) true RMS, ac coupled. - Resistance, in two-wire (Ω-2 W) and four-wire (Ώ-4 W) configuration - Temperature °C Ranges can be selected manually, automatically or remote. Beside the standard functions the user can alter the speed to increase the number of measurements per second, or to obtain a higher resolution. The filter function switches in a frequency filter in the function and A~; in all other functions (except °C) it acts as a digital filter. Offset in the lowest dc range can be compensated by using the NULL function. Measurements can be started with an internal, manual or external facility. External starting is possible via the trigger input, or via the IEC/IEEE-bus interface. The help functions (green text) are: - Mathematical functions, processing the measuring data such as: AX + B Δ% dBm ZERO - Aquisition/presentation of the measuring data such as: DELAY, LIMITS, BURST. RD.BUF, MIN/MAX, LIMITS, DIGITS - Function programming such as: To store and call combinations of instrument settings. PROG, SEQU (SYSTEM 21) - General Beeper on/off, CHECK, ENTER, CLR (CLEAR)