They are also the most limited in frequency capabilities, often just spanning the audio range.
The black boxes are next in cost and have the advantage of portability and low power.
You can calculate the RMS voltage V for a given d Bm value and resistance R in from the following equation: For example, a 0 d Bm signal into 50 represents an RMS voltage of 0.2236 volts, but represents 0.7746 volts into a 600 load.
is the phase of the sine wave (in the graph, the sine wave is shown with a phase of 0).Two other measures of a sine wave's amplitude are often used: RMS and peak-to-peak voltage.This guidebook is useful to those with little knowledge of function generators, as well as the experienced technician or engineer who wishes to refresh his/her memory or explore new uses for function generators and more sophisticated arbitrary waveform generators.First, we will explain the controls of a typical function generator.This relationship to the amplitude only applies to sine waves.
Another measure used for the amplitude is the peak-to-peak voltage DDS function generators may have the ability to let the user set the amplitude using the peak-to-peak voltage or the RMS voltage.
The testing of physical systems and transducers often needs stable and reliable signals.
The signal levels needed range from microvolts to tens of volts or more.
The more expensive dedicated instruments add features and usually include one or more types of interface connections that allow computer control.
The B&K Precision model 4040DDS function generator shown on the following page is a representative of modern DDS function generators.
We will describe the numbered controls and their functions.