Frequency composition in naval communication transmitters

The demand for improvement in Naval transmitters during the early stages of the war led to the adoption of a frequency-composition system for the control of frequency. The system here described provides complete flexibility of the generated frequency with a stability of the same order as that of direct crystal control, and has many incidental advantages. The most important of these is the possibility of accurate and direct frequency calibration. The main disadvantage lies in the production of unwanted frequencies that are not harmonically related to the required frequency. A full treatment of the mechanism of generation of these frequencies, and of methods by which they can be reduced, is given. The application of the system to certain standard Naval equipment is also described.