Topic: Microwave Engineering
Multiple collectors are used in Travelling Wave Tube (TWT) to
- A. to distribute the dissipated heat evenly
- B. to increase the overall efficiency
- C. to increase the gain of the TWT
- D. to shape the electron beam
Answer: B. to increase the overall efficiency
Explanation: TWT is basically a wideband amplifier in which the interaction space is extended and the electron beam exchanges energy with the RF wave. The efficiency offered (dc to RF) is about 10%. TWT efficiency can be increased by the use of multistage collectors at the end of the electron beam's path that are biased at voltages lower than the accelerating anode voltage.