Types, Performance and Applications of Different Tubes
Prof. Dr. Md. Mostafizur Rahman
Klystron Amplifier Performance and Applications
Application &
Requirement
Frequency Range (GHz)
Needed Power, Max.
Available Power, Max.
UHF TV Tx (CW) 0.5-0.9 55 KW 100 KW
Long range radar (Pulsed) 1.0 - 12 10 MW 20 MW
Linear particle accelerator (Pulsed)
2.0 – 3.0 25 MW 40 MW
Troposcatter links (CW) 1.5 - 12 250 KW 1000 KW
Earth Station transmitter (CW)
5.9 - 14 8 KW 25 KW
Applications of Klystron Oscillator:
- Signal source in microwave generator - Local oscillator in microwave receivers
- Frequency modulated oscillator in portable microwave links.
- Pump oscillator for parametric amplifiers
Types, Performance and Applications of TWT
1. Broadband - Low noise, low level amplifiers used mainly for receivers.
Weight about 1.5 kg, Dimension 30x5x5 cm
2. CW power TWT – Weight about 2.75 kg,, Dimension 7x7x41 cm, Uses in Satelleite communications and its earth station, Radar.
3. Pulsed TWT – Quite bigger and more powerful than above twos. , Weight about 20 kg and dimension 53x15x20 cm.
4. Dual Mode- Weight about 4.5 kg and 45 cm long.
Name and model Frequency Range (GHz)
Power Output, Max.
Power Gain, dB
Broadband TWX19 7-12 1 mW 38 KW
CW Power TWT Hughes 677H Hughes 614H Hughes 870H Hughes 819H
5.9-6.4 5.9-6.4 14.0-14.5 54.5-55.5
125 W 8KW 5 kW 5 KW
45 40 35 20 Pulsed TWT (Hughes 797H) 8-12.5 9 KW
Dual Mode (Hughes 562H) 2-4 200W/1 KW 30/30
Types, Performance and Applications of Magnetron
1. (Vane type)Conventional metal ceramic magnetron (Pulse) – 20 Kw output power. Weight about 2 kg, Hight about 2 m. Current use in marine Radar, produces about 25 KW pulsed in X band.
2. Coaxial magnetron (Pulse) – 5 MW at 3 GHz,
3. Frequency agile or dither-tuned – It may be conventional or coaxial. It is useful for Radar.
4. Voltage tunable Magnetron (VTM) – Frequency range 200 MHz to X band, power up to 1000 W, Higher efficiency, up to 75%, This tubes are used in sweep oscillator, in telemetry and missile applications.
5. Fixed Frequency CW magnetron- It extensively used for industrial heating and microwave ovens. Operating frequency are 900 MHz to 2.5 GHz., Output power 300 W to 10 Kw, Efficiency is about 70%.
Reference:
Electronic Communication Systems - Kennedy
