voltage, e.g. adjustable between -5V to +5V. An output impedance of . Software A completely different approach to function generation is to use software instructions to generate a waveform, with provision for output. For example, a general-purpose digital computer can be used to generate the waveform; if frequency range and amplitude are acceptable, the sound card fitted to most computers can be used to output the generated wave. Circuit elements Waveform generator An electronic circuit element used for generating waveforms within other apparatus that can be used in communications and instrumentation circuits, and also in a function generator instrument. Examples are the Exar XR2206 and , which can generate sine, square, triangle, ramp, and pulse waveforms at a voltage-controllable frequency. Function generator An electronic circuit element that provides an output proportional to some mathematical function (such as the square root) of its input; such devices are used in feedback control systems and in analog computers. Examples are the Raytheon QK329 square-law tube and the Intersil ICL8048 Log/Antilog Amplifier. Mechanical function generators Mechanical function generators are linkages, cam-follower mechanisms or non-circular gears, designed to reproduce different types of functions, either periodic (like sine or cosine functions), or single-shot (logarithm, parabolic, tangent functions etc.). Measurement instruments like pressure gauges, altimeters and barometers include linkage-type function generators as linearization means. Before the advent of digital computers, mechanical function generators were used in the construction of gun fire control systems, and mechanical calculators. See also Digital Pattern Generator Electronic musical instrument Wavetek References External links Function Generator & Arbitrary Waveform Generator Guidebook Waveform Generator Fundamentals Function Generator Fundamentals . History of the function generator. Electronic test equipment