Abstract: A system for generating a radio frequency signal phase-locked to a reference signal. Such a system includes a rotary travelling wave oscillator including a conductive ring and a plurality of sustaining amplifying cells electrically connected to the ring; a programmable multiplexer device designed to electrically connect an input port of the system to an amplifying cell that can be selected from the cells of the plurality. The system is designed so that the oscillator generates the locked radio frequency signal when the reference signal is injected at the input port of the system. A phase difference between the radio frequency signal and the reference signal is a function of the amplifying cell to which the input port is electrically connected via the programming of the multiplexer device.

Abstract: Disclosed are methods and devices for predictive maintenance of at least one component of a road vehicle. The general principle is based on the combination of the ranges of values of parameters that represent the wear of a road vehicle component. The method includes observing the duration of use of combinations of ranges of values in order to deduce therefrom a wear profile which is compared with a predetermined wear profile. This mechanism makes it possible to reduce the amount of information to be stored.

Abstract: An entry into an acceleration phase of the vehicle is detected, the ignition advance of the engine is then reduced to a predetermined value (a.sub.L) and the advance is maintained at this value for a predetermined time interval (.DELTA.t) which is a function of the selected gear ratio (r) of a gearbox placed on the output side of the engine.Application to a vehicle propelled by an internal-combustion engine associated with an ignition- and injection-control computer.