Abstract: An object circuit for use in an r.f. identification system for locating a specific object by generating identification signals of a specific frequency assigned to a given object, said object circuit including a receiving antenna, a crystal coupled to said receiving antenna, said crystal having a resonant frequency equal to the frequency assigned to the associated object, and circuitry coupled to said crystal for responding to a signal of said assigned frequency received by said object circuit.

Abstract: A data token with extended operational lifetime incorporates operational circuitry requiring D.C. power, a battery for supplying D.C. power to the circuitry, a power switch coupled between the battery and the circuitry, and a frequency selector for sensing remotely generated signals and for operating the switch when such signals are received so that D.C. power is applied to operate the circuitry only when the remotely generated signals are sensed in order to confine energy drain from the battery to only those periods when circuit operation is needed and extend the useful lifetime and range of the data token. The frequency selector is a crystal having a specific resonant frequency which only responds to remotely generated signals of the matching frequency. The switch is an FET switch. An integrator circuit is coupled between the frequency selector and the FET switch to smooth the D.C. voltage developed by the crystal.

Abstract: A laptop computer has a first relatively powerful and fast data processor and a second relatively slower data processor. The first data processor has a higher power consumption factor than the second. A switch mechanism controls which of the two processors is operatively connected to the computer system components. When external power is available, the faster more powerful processor is used. When external power is unavailable and the computer must be operated from the internal power source, the second processor is used to drive the system components in order to provide a longer total operating duty cycle before the internal power source is exhausted.