Properties:

An electronic device consisting of the necessary elements to establish the frequency or frequency range of two or more tuned circuits to predetermined value or range. It may have facilities for calibration adjustments. There are no integral facilities for continuous variation of the frequency over the entire range of the item. It is generally used with an external variable capacitor or inductor which will effect the continuous variation of the frequency. This item is used to facilitate rapid band or channel changes in radio receivers, transmitters, amplifiers or similar devices. It does not include electron tubes. See also coil assembly, radio frequency and tuner, radio frequency.