We think of crystals as the gold standard of frequency generation. However, if you want real precision, you need something either better than a crystal or something that will correct for tiny ...

Fortunately, the function generator accepts an external clock ... used the NIST WWV broadcast and his ears to find when his frequency standard overlapped that of the source, therefore verifying ...

The 1510A Precision Signal Source generator available from MTI Instruments is a compact and portable device and includes dual-channel Direct Digital Synthesis (DDS) that creates high precision signals ...

But because high frequencies have shorter range than lower frequencies, 5G uses a mix of network frequency bands, generally classified as high, medium, and low.