Koninklijke Philips Corporation N.V.

Nxp B.v.

Hendricus Martinus Van Der Wijst

Kam Choon Kwong

Yeow Teng Toh

Ernst Bressau

Henk Leeflang

Ernst B Bressau

Detlef Horst Marbach

Erwin Arnold

Guenther Spee

The invention relates to a method for determining the strength of a signal () at the input of a tuner (.) In this, the frequency-dependent amplification characteristic for the tuner is measured and stored in a memory assigned to the tuner. With the help of this characteristic the frequency-dependent variation of the amplification can be compensated during tuner operation, in order that the input signal strength can be deduced more precisely. For a tuner with automatic gain control (AGC), the frequency dependence of the AGC can also be recorded and stored in the memory by representative characteristics. The consideration of the AGC characteristics results in a further improvement to the precision of estimation of the input signal strength.

Method for determining the signal strength at the input of a tuner

The invention relates to a television signal receiver comprising a radio-frequency tuner () and at least one subsequent surface-acoustic wave filter (), in which the radio-frequency tuner () filters a RF television signal applied to its input and converts it to an intermediate-frequency television signal which is coupled to the surface-acoustic wave filter (). The RF tuner () has at least one output stage () which supplies the IF television signal converted to the intermediate frequency. The output stage () is directly connected to an output () of the RF tuner (), while a switch () is associated with it, by means of which switch the IF television signal is supplied to a second output (). A further switch () is associated with the second output (), by means of which switch the associated output () is switchable to a fixed reference potential. The RF tuner () precedes at least one surface-acoustic wave filter (), in which each time a first input () of the surface-acoustic wave filter () is coupled to a first output () of the RF tuner (), and a second input () of the surface-acoustic wave filter () is coupled to the second output () of the RF tuner () via the first switch (), and, for switching the filter characteristic of the television signal receiver, alternately the second input () of the surface-acoustic wave filter () can be coupled to the same IF television signal by means of the associated switch ().

Television signal receiver with a universal output for surface-acoustic wave filters of different types

A bipolar transistor (Tr) in an oscillator stage of a tuner is provided with a diode (D) in series with a resistor (R) coupled between the base of the transistor (Tr) and the reference voltage to which the emitter of the transistor (Tr) is coupled. The diode (D) allows a decreased resistor (R) value which causes the supply voltage ripple (Vr) on the collector originating from the base to decrease so as to better compensate the supply ripple (Vr) on the collector directly originating from the supply voltage (Vs.).

Power supply ripple rejection in tuner oscillator stage

An interface module for receiving television signals or radio signals has several inputs and outputs for receiving and distributing picture and sound signals as well as control signals and at least one input for antenna signals. The interface module includes at least one tuner and a chip with a microprocessor including memory and data capture capability, and is capable of picture, color and sound decoding and signal processing units. The chip and the tuner are installed in a common casing.

Interface module for TV sets

The present invention relates to a coil ( ) having a plurality of turns ( ). The characteristic feature of the invention is that the turns ( ) include a magnetic material or the turns ( ) have an outer layer for carrying an electric current and have a magnetic material in their interior.

Growing community of inventors

Veldhoven, Netherlands

Hendricus Martinus Van Der Wijst