Abstract: A digital frequency multiplier which includes a first counter for counting the number of clock pulses received from a generator having first been divided by N in a divider. The counter establishes the number of these pulses which occur during a cycle of the incoming frequency and this number is compared in a comparator with the count from a further clock counter. Typically when coincidence occurs a change of state of the comparator results and as this coincidence will occur N times during a cycle of the incoming frequency, the output repetition frequency from the comparator will be N times the incoming frequency. Although division can be provided prior to the first counter this can alternatively be provided after this counter by using an arithmetic divider.