Abstract: The object of the invention is a transmitter/receiver for transmitting and receiving of an RF signal in two frequency bands. In the solution according to the invention, a transmitter/receiver is used which is based on direct conversion and in it, when operating in both frequency bands, the mixing frequency is formed by means of the same synthesizer (340). This is implemented preferably in such a way that in the higher operating frequency, the frequency of the output signal of the synthesizer is used as such as a mixing frequency and when operating in the lower operating frequency, a mixing frequency is used which is obtained by dividing the frequency of the output signal of the synthesizer by two or a larger integer in the divider (311, 361). When the solution according to the invention is used, many synthesizers are not needed in the transmitter/receiver and no intermediate frequency components are needed.

Abstract: This invention teaches a method, and circuits that operate in accordance with the method, for adaptively controlling the transmitted power of a CDMA transmitter (50, 102). The method includes the steps of: (a) presetting a register, such as a counter (112), with an estimate of a maximum transmitter gain signal, the counter having an count output that is a representation of a maximum transmitter gain signal (TX max); (b) deriving a transmitter gain signal (TX gain) from a received CDMA signal; (c) comparing TX max to TX gain and, if TX gain is greater than TX max, (d) applying a gain control signal to the transmitter that is derived from TX max, and (e) enabling the counter to increase its count; else, if TX gain is less than TX max, (f) applying a gain control signal to the transmitter that is derived from TX gain, and (g) disabling the counter from increasing its count.

Abstract: A dual mode transmitter circuit is disclosed including a non-linear high-power amplifier having an amplification that can be adjusted and a linear high-power amplifier. A first switch and a second switch are connected to the input and output of the linear, high-power amplifier. An amplification-adjustable, high-frequency transmitter control amplifier is connected to the input of the non-linear high-power amplifier. Apparatus for measuring transmission power such as a directional coupler is connected to the second switch, and a duplex filter is connected to the directional coupler. A power level control circuit is responsive to the measured transmission power from the directional coupler and to a power level signal. The power level signal is representative of the desired output power of the transmitter.

Abstract: The present invention relates to a circuit arrangement by which a voltage-controlled temperature-compensated oscillator (VCTCXO) (10) serving as the frequency reference in a radio telephone is controlled. In the circuit arrangement there is used a phase-locked loop which locks the frequency of the VCTCXO (10) to the frequency of the intermediate-frequency signal (2.IF) of the receiver of the telephone. When the telephone is started up, a constant setting voltage (30) is coupled as the control signal (V.sub.con) for the VCTXCO (10) for controlling the reference frequency. In the call state the control signal (V.sub.con) is provided by by the phase-locked loop in which the locking is to the frequency of the intermediate frequency signal. When the call is cut off the control voltage (V.sub.con) is supplied from a memory (26) coupled to the phase-locked loop in which the value of the control signal (V.sub.con) is substantially equal to the control signal (V.sub.

Abstract: A hand-held transceiver comprises a base element and an amplifying element between which there is a defined interface, whereby the beam element may alternatively be connected with the separate amplifier through the above mentioned interface. Due to the modular structure of the hand-held transceiver, it is possible to make a car radio telephone where the hand-held transceiver connected to the amplifier only comprises the base element.

Abstract: An arrangement for mounting and supporting of a shank of a drilling machine comprising a body supported by a carriage, a percussion piston mounted in the body, and supporting housing positioned at a front side of the body, and a shank piece mounted in the supporting housing as an axial extension of the percussion piston. In order to reduce the strains exerted on tie rods of the body of the drilling machine, the supporting housing of the shank is supported at least partly by the carriage separately from a support between the body and the carriage so that the sideward forces acting on the shank are received directly by the carriage through the supporting housing.

Abstract: An arrangement for supporting of an axial bearing of a drilling machine which comprises a body (1) supported by a carriage (15) and a rotation bushing (5) mounting rotatably in the body for rotation of a shank (10). An axial bearing (8) is arranged in the body for receiving axial forces (F) acting on the body through the shank. In order to release the body from strains caused by the axial forces of the shank, the axial bearing is supported on the carriage by a supporting device (16) for transmitting of the axial forces from the axial bearing directly to the carriage.

Abstract: An arrangement for mounting of a rotation element in a drilling machine comprising a body (1) and a rotation element (8) mounted by means of bearing surfaces (8a, 8b) rotatably in the body for rotation of a drill shank (9). The rotation element is rotated by a rotation machinery (10) in engagement with a gear ring (11) of the rotation provided in the rotation element between the bearing surfaces. In order to replace the rotation element without having to disassemble the body, the rotation element is mounted at both ends thereof in the radial direction in an integral body part (3), and the bearing surfaces and the gear ring are arranged in a stepped manner so that the rotation element is removable from the integral body part axially through one end (3c) thereof.

Abstract: A body construction for a drilling machine comprising a body provided with end covers, a percussion means mounted in the body, and a rotation means positioned on an axial extension of the percussion means for rotating a shank. In order to avoid the use of conventional tie rods, the body is formed by an integral body part, and housings for the percussion and the rotation means are formed in the body part in such a way that the percussion and the rotation means can be replaced through the corresponding end covers without having to detach from the body anything else but the end covers of the body part.

Abstract: A bearing arrangement for a feeding device for a drilling machine, comprising a feeding beam (1) provided with longitudinal guides (6), a carriage supporting a drilling machine (3) and provided with guide surfaces in slidable engagement with the guides, and displacing means for displacement of the carriage along the guides. At least one guide surfce (5a) of the carriage is formed by a spacer (5) supported by the carriage. For automatical eliminatin of the clearance between the feeding beam and the carriage, the spacer is pressed against a wedging surface (8) provided on the carriage and extending essentially in parallel with the guide. The carriage is provided by means (9) for displacement of the spacer in between the guide surface (6a) of the guide of the feeding beam and the wedging surface (8) of the carriage so that the growth of clearance caused by wearing of the spacer is avoided as the wearing increases.

Abstract: A drill steel centralizer comprising a body having an immovable jaw positioned in stationary relation to the body. A movable jaw and drill steel guide between said jaws that can be opened and closed by means of the movement of the movable jaw. A locking device providing means by which the movable jaw can cause the drill steel guide to be locked and released into the closed and open positions. Thus, the locking device is held in its locked position by an elastic member that is arranged to transmit a force attempting to open the jaw past the elastic member directly to the body.