Marine VHF transceiver and switchable frequency source - uses single quartz oscillator delivering series of pulses at stable frequency

摘要

The VHF switchable frequency source has a quartz oscillator. This oscillator is designed to deliver a very stable frequency in the form of pulses. The frequency source has also frequency processing circuit. This circuit has at least a digital controlled frequency synthesiser. The circuit is coupled to the quartz oscillator so as to furnish a gradual frequency of the pulse output of the quartz oscillator. A pulse output modulator circuit is coupled to the quartz oscillator and to the frequency processing circuit. This modulator provides on output frequency tied to the frequency of the quartz oscillator. This output frequency is however shifted according to the gradual frequency. A digital control means is designed to control the frequency synthesizer.