[Debraj] needed a simple signal generator for a project he was working ... he observed that the PC had good frequency fidelity, though it required an additional DC offset as most cards are built ...

10 MHz output from DIY frequency standard Of course ... his relatively affordable Siglent SDG 1025 Arbitrary Function Generator, but found its accuracy to be a bit lacking.

A waveform generator is available as a bench top instrument, portable, or PC based module. An arbitrary waveform generator ... and also for producing alternating current of desired frequency and ...