The Use of Mode A for Improving Power Properties of Band Capacity Amplifiers of Millimeter and Decimeter Waves

The transistors of the output stages of band capacity amplifiers operate as a rule in the collector cutoff operating mode. However, under the small stage amplification factor, the power applied to this output is commensurable to the output power. In this case, advantages of the transistor cutoff operating mode become disputable. It is shown that if the stage amplification factor is smaller than 8 dB it is preferred to use the operation mode without cutoff to increase its efficiency. In this case, the improvement of power properties is realized due to the increase of the stage amplification factor by 6 dB. In the article, the design of a functional scheme of band capacity amplifiers working without cutoff is proposed. Amplifiers built according to this functional scheme possess the following advantages: bigger efficiency under the constant output power; ability to work for reflecting load in the input overcharge conditions; ability to increase by 1.5-3 times the upper operating frequency of the band capacity amplifier with using the given transistor