Frequency synthesis (FS) is a technique vital for all kinds of radio frequency (RF) communications, such as: mobile phones, Bluetooth, Wi-Fi, radio, TV and satellite, and in other equipment requiring periodic signals of stable and programmable frequency. In this work, we present a generalization of the FS technique to random, non-periodic signals, whose main use is in the new area of stochastic neuromorphic computing and, information security and instrumentation. Since conventional FS circuits cannot work with random signals, we introduce a novel random frequency ratio detector, that works both with random and periodic signals.