Simple standard frequency generator - has oscillator tuned to harmonic of synthesiser whose reference frequency output is set incrementally by microprocessor

摘要

The standard frequency generator has a phase controlled oscillator tuned to the m-th harmonic of a variable reference frequency fr. Its output frequency fa must be tuned with an accuracy of fa. The reference frequency fr is the output frequency of synthesiser whose frequency can be set in decades and whose output frequency fr' in the lowest decade is set in frequency steps of fa. The synthesiser setting device has a microprocessor by which the synthesiser is set to that reference frequency fr' which produces the output frequency fa' = mfr' nearest to the required frequency fa.