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The PCI-305 25 MHz Sine Wave Generator and 50 MHz Clock Generator is a PC-Based (ISA Expansion Card) Generator that uses Direct Digital Synthesis techniques to create sine waves from 1Hz to 25 MHz, and TTL Clock Signals from 0.1Hz to 50 MHz. The sine wave output amplitude can range from 24Vpp down to 100 mVpp (12Vpp to 50mVpp with a 50 Ohm load), and the DC offset is adjustable from +12Volts to –12Volts (+6Volts to –6Volts with a 50Ohm load). The total output voltage (DC plus Peak AC) is ±12Volts for the sine wave output. The DC offset and amplitude controls each have three digits of settability. For more information, download the .pdf of the complete, detailed data sheet and specifications.

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25 MHz Sine Wave Output - Separate TTL 50 MHz Sync Output - 24 Vpp - Direct Digital Synthesis Frequency Control

The PCI-305 uses a Direct Digital Synthesis (DDS) circuit to control its output frequency. The DDS technique has three advantages over phase-lock-loop (PLL) designs and other frequency control schemes. First of all, frequency changes occur without any phase discontinuities (as opposed to the frequency overshoot and settling errors that occur in PLL based generators). Secondly, the frequency is settable in increments of 29 MHz, thereby allowing very fine frequency adjustments. The third advantage is that the execution time of a frequency change command combined with the time it takes the generator to change frequency is as little as 10 us. This fast frequency change response makes it possible to combine your software with the PCI-305 to create a Sweep Generator, Frequency Hop Generator, or a smart Frequency Response Analyzer that uses search algorithms to find peaks in the frequency response of a circuit or system. The standard frequency accuracy is 25 ppm, but better frequency accuracy is available. Contact the factory for the latest details.