This manual is for both the TG2000 and TG1000 function generators. The TG1000 has a maximum frequency of 10MHz and no remote control capability but is otherwise functionally the same as the TG2000 20MHz generator. Wherever there are differences in the specification or operation, the limits for the TG1000 are shown in square brackets [ ] after the TG2000 limits. This function generator uses direct digital synthesis to provide high performance and extensive facilities at a breakthrough price. It can generate a variety of waveforms between 1mHz and 20MHz [10MHz] with a resolution of 6 digits and an accuracy better than 10ppm. Direct digital synthesis for accuracy & stability Direct digital synthesis (DDS) is a technique for generating waveforms digitally using a phase accumulator, a look-up table and a DAC. The accuracy and stability of the resulting waveforms is related to that of the crystal master clock. The DDS generator offers not only exceptional accuracy and stability but also high spectral purity, low phase noise and excellent frequency agility. A wide range of waveforms High quality sine, square and pulse waveforms can be generated over the full frequency range of 1mHz to 20MHz [10MHz]. Triangle waveforms can also be generated but with limitations as to the maximum usable frequency. Variable symmetry/duty-cycle is available for squarewave and pulse waveforms. Sweep All waveforms can be swept from 0.2Hz to their maximum frequency in a single sweep at a rate variable between 50 milliseconds and 999 seconds. The sweep is fully phase continuous. Sweep can be linear or logarithmic, single or continuous. Single sweeps can be triggered from the front panel, the trigger input, or the digital interfaces. A sweep marker is provided. AM External Amplitude Modulation is available for all waveforms. FSK and Tone modes Frequency Shift Keying provides phase coherent switching between two selected frequencies; in Tone mode the output is stepped asynchronously through a user-defined list of up to 16 frequencies. In both modes the switching source can be the internal trigger generator, front panel, an external signal or a remote command. Easy and convenient to use All of the main generator parameters are clearly displayed together on a backlit LCD with 4 rows of 20 characters. Sub menus are used to set the parameters for each function. All parameters can be entered directly from the numeric keypad. Alternatively most parameters can be incremented or decremented using the rotary encoder. This system combines quick numeric data entry with quasi-analogue adjustment when required. Fully programmable via USB and Addressable RS-232 (TG2000 only) The generator has both USB and RS-232 interfaces which can be used for remote control of all of the instrument functions. As well as operating in conventional single instrument mode the RS-232 serial interface can also be used in addressable mode whereby up to 32 units can be linked to a single PC serial port.