NOVATECH INSTRUMENTS is a manufacturer of Direct DigitalSynthesizer (DDS) Signal Sources, Rubidium Frequency Standards and QuartzFrequency Standards.
A knockoff Arduino Nano controls a generic AD9850 direct digital synthesizer circuit, both plugged into standard 0.1 inch headers, with hand-wiring connections below the proto board. The SMA connector provides a mechanically rugged output from the board; the DDS frequencies don’t require its RF properties.
Answers to some questions about direct digital synthesis (DDS).
Of course, nothing is ever so simple as it seems. In this article, I’ll explain how numeric precision affects Direct Digital Synthesis (DDS) output frequency calculations, work through the effects of floating-point and fixed-point arithmetic, and show how a carefully tweaked DDS oscillator frequency varies with temperature.
Linear interpolation in direct digital synthesis - Stack Overflow
Nicholas and Henry Samueli, "An analysis of the output spectrum of direct digitalfrequency synthesizers in the presence of phase-accumulator truncation,"in