Abstract: A method is presented for minimizing the current consumption and the operating voltage of a voltage controlled oscillator. According to the invention the oscillator's (Q2) output signal (RFout) is detected as a DC voltage signal (Vgs) in a clamp/voltage multiplier circuit (U1, U2), preferably after a isolating amplifier (Q1). This detected signal is supplied in a feedback loop to a field effect transistor (FET1) controlling the oscillator's (Q2) current, whereby the field effect transistor controls the current (Ib) in the main current path to a predetermined minimum value. In this superimposed arrangement of the oscillator and the isolating amplifier the supply voltage (B) can be minimized by arranging, regarding the DC current, the isolating amplifier (Q1) in parallel with the field effect transistor (FET1) in the emitter branch of the oscillator (Q2).

Abstract: The invention concerns oscillator circuits, more particularly coupling arrangements between an oscillator and an amplifier stage following the oscillator. The solution according to the invention optimizes the intensity of the coupling between the oscillator and the following amplifier stage so that the desired output level of the oscillator circuit is gained but the oscillator is loaded as little as possible. In the system according to the invention, the impedance value of the circuit element between the oscillator and the amplifier stage has been arranged to be automatically adjustable so that it is always adjusted to its smallest value, on which the desired output level of the oscillator coupling can still be gained. The coupling can, for example, be formed by means of a capacitance diode, the bias voltage of which is adjusted according to the direct voltage detected at the output level of the amplifier stage.

Abstract: The invention is related to an electrically tunable voltage-controlled oscillatory circuit, wherein the negative bias voltage (-Vcf) of a capacitance diode (5) needed for tuning the center frequency of the oscillatory circuit is generated on the basis of an electric oscillating signal (RFout) produced by the oscillatory circuit itself. Said oscillating signal is used for generating a negative voltage with a clamp/voltage multiplier type circuit (15) and it is adjusted to a desired value with an adjustment circuit (14), in which the values of the components (R2) can be permanently adjusted suitable in the tuning stage. Alternatively, the adjustment circuit (14) may include an active component (Q1) which can have an effect on the value of the negative bias voltage (-Vcf) during the use of the oscillatory circuit.

Abstract: The object of the invention is a circuit for monitoring the power of a transmitter amplifier. In the solution according to the invention, the detected DC voltage level (V.sub.det) corresponding to the output power is compressed at high output levels by using as the coupling capacitance a capacitance diode (7) such that the capacitance of this component, and thereby the tightness of the coupling, diminishes as the detected voltage level increases. The invention can be employed, for example, in the power control of a mobile phone's transmitter.

Abstract: A resilient connector for radio frequency signals comprises contact pins (1-3) perpendicularly movable in holes (12-14) made into a printed board (10). Each pin is connected to a circuit through a signal spring (4-6) with one end rubbing against the pin (1-3). The contact between the pin and an other connector is secured by a helical spring (7-9) pushing the pin away from the board (10).

Abstract: A low impedance surface connector is arranged on a printed board (10) with printed contacts (1-6) formed by the printed conductors. The contacts (2, 3; 5, 6) for the ground and the sheath are situated in conducting relationship symmetrically on both sides of the signal contact (1; 4) in the plane of the printed board surface (11, 12).