Aligning method for a multistage selective amplifier and circuit arrangement for carrying it out

Claim 2

Method for calibrating a multi-stage selective amplifier which can be tuned by means of several reactance elements which can be driven independently of one another, particularly a tuner, characterized in that the selective amplifier (14), particularly the tuner, is calibrated by an external calibration device (15) by means of a microcomputer (16) for controlling the entire calibration process, a signal generator (17) controlled by means of a phase-locked loop, for generating automatic calibration signals, and a store (18) via the reactance elements (1 to 8) in that the calibration values needed for driving the individual reactance elements (1 to 8) are determined in iterative calibration steps and are in each case temporarily stored in the store (18) and in that after optimization and termination of the calibration process, the final calibration values are transferred into a non-volatile store (11) of the selective amplifier (14), particular of the tuner, where they are permanently stored for its later operating state.

Claim 3

Method according to Claim 1, characterized in that the individual stages or circuits of the selective amplifier (14) are calibrated successively and independently of one another.

Claim 4

Method according to Claim 1 or 2, characterized in that the selective amplifier (14) is calibrated in each nth (n > 1) frequency channel and the corresponding calibration values are permanently stored in the amplifier.

Claim 5

Method according to Claim 3, characterized in that n is varied in dependence of the characteristic curve of the reactance elements (1 to 8) in a range n L- 2.

Claim 6

Method according to Claims 3 or 4, characterized in that the calibration values for the frequency channels not stored are determined in the operating state of the selective amplifier (14) by linear interpolation of the values permanently stored for the adjacent channels.

Claim 7

Method according to one or more of Claims 1 to 5, characterized in that only the difference values with respect to the absolute calibration value for the reactance elements (4, 8) of the oscillator circuits of the selective amplifier (14) are permanently stored as calibration values for the reactance elements (1 to 3 and 5 to 7) of the RF and IF circuits.

Claim 8

Arrangement for carrying out the method according to one or more of Claims 1 to 6, for calibrating a multistage selective amplifier which can be tuned by means of several reactance elements which can be driven independently of one another, particularly a tuner, characterized in that the selective amplifier (14), particularly the tuner, can be connected to an external calibration device (15) which contains a microcomputer (16) for controlling the entire calibration process, a signal generator (17), controlled by means of a phase-locked loop, for generating automatic calibration signals in the form of mono-frequency marker signals corresponding to the information carriers of the pass curves of the selective amplifier, particularly the tuner, and a store (18) for temporarily storing the calibration values obtained in iterative calibration steps for the individual reactance elements (1 to 8), and in that the selective amplifier (14), particularly the tuner, is equipped with a non-volatile store (11) into which the calibration device (15), after completed calibration of all frequency channels, transfers the optimized calibration values which can be permanently stored there for the later operating stage of the amplifier (14), particularly the tuner.

Claim 9

Arrangement according to Claim 7, characterized in that the calibration device (15) has an additional adjusting device (19) which can be manually operated.

Claim 10

Arrangement according to Claim 8, characterized in that the adjusting device (19) is constructed in the form of several potentiometers.

Claim 11

Arrangement for carrying out the method according to Claim 5, characterized in that in the operating state of the completely calibrated selective amplifier (14), an already existing microcomputer (13) is connected instead of the calibration device (15), which takes over the linear interpolation for determination of the calibration values not stored.