Abstract: An amplifier comprising at least one amplifying element (20a, 25a) and a biasing circuit (32a, 32b) for biasing the or each amplifying element with a bias voltage is disclosed. The biasing circuit (32a, 32b) is adapted to vary the bias voltage such that the or each amplifying element switches between non-switching and switching modes of operation in response to a bias control signal (4) passing through a threshold value.

Abstract: An amplifier comprising at least one amplifying element (20a, 25a) and a biasing circuit (32a, 32b) for biasing the or each amplifying element with a bias voltage is disclosed. The biasing circuit (32a, 32b) is adapted to vary the bias voltage such that the or each amplifying element switches between non-switching and switching modes of operation in response to a bias control signal (4) passing through a threshold value.

Abstract: A radio receiver is selectively operable in a current mode or a voltage mode according to conditions prevailing within a wireless environment. If the signal levels within the wireless environment are relatively low, the radio receiver is operable in current mode. If the signal levels within the wireless environment are relatively high, the radio receiver is operable in voltage mode. The radio receiver is switchable between current and voltage mode of operation via selectively actuable switches that bringing into effect or remove from effect corresponding resistances.

Abstract: Embodiments of the present invention relates to an integrated mixer. A problem with producing low power consumption mixers is that they require a relatively high operating voltage due to the number of layers of transistor between the power rails.

Abstract: Embodiments of the present invention relate to a voltage controlled oscillator having a substantially constant modulation index. The oscillator uses a plurality of MOS varactors to, firstly, select the centre frequency of oscillation of the modulator and, secondly, to control the degree of modulation of that frequency.

Abstract: Embodiments of the present invention relates to an integrated mixer. A problem with producing low power consumption mixers is that they require a relatively high operating voltage due to the number of layers of transistor between the power rails.

Abstract: New polymer supports containing cleavable cross-links are described which are suitable for solid phase peptide synthesis and can then be solublized for further chemical or biological manipulation (including immunization) in solution.