Tuning system which produces control signals - which denote quality of reception of signals from transmitters

The tuning system has a signal test circuit producing a control signal describing the receive quality of a transmitter received at the antenna input. A changeover device changes over the signal input of the mixer from the output of the spectrum generator to the antenna input, the tuning of the mixer oscillator is stopped, and the signal test circuit is set into operation when a discriminator produces a signal having a desired value. The changeover device changes back and the tuning of the mixer oscillator enabled when the signal test circuit produces a control signal describing a poorly received transmitter or when the switch triggering the sweep mode is operated.