The 8974 is a power tetrode designed for very high powered frequency or high frequency broadcast service and very low frequency communication in the megawatt power range. The 8974 has a two section thoriated tungsten filament mounted on water-cooled supports. The two sections may be fed in quadrature to reduce hum contributed by an arc ac power source. The maximum anode dissipation rating is 1500 kW steady state. Large diameter coaxial terminals are used for the control grid and the RF filament terminals. Filament power and filament support cooling water connections are made through three special couplings with threaded clamping rings. Characteristics Plate Dissipation (Max.) Screen Dissipation (Max.) Grid Dissipation (Max.) Frequency for Max. rating (CW) Amplification Factor Filament/Cathode Voltage Current Capacitance Input Output Feedthrough Capacitance Input Output Feedthrough Cooling Base Air Socket Air Chimney Boiler Length Diameter Weight 1,500 Kilowatts 15.0 Kilowatts 4.0 Kilowatts 30 MHz 4.5 Thoriated Tungsten 16.3 Volts 600 Amps Grounded Cathode 1600 pf 250 pf 6.0 pf Grounded Grid 675 pf 260 pf 1.0 pf Water and Forced Air Special Coaxial N/A N/A N/A 23.75 in; 60.30 cm 17.03 in; 43.30 cm 175.0 lb; 80.0 kg Maximum RatingsTypical Operation Class of Type of ServicePlate PlatePlateScreenPlate Operation VoltageCurrent Voltage VoltageCurrent (Volts) (Amps) (Volts) (Volts) (Amps) C RF Amplifier C RF Amplifier Plate Modulated AB1 RF Linear Amplifier AB1AF Amplifier or Modulator 22,500 17,500 22,500 22,500 125 100 125 125 21,500 17,500 20,000 17,500 1,000 1,000 1,500 1,500 125 95.0 86.5 146 Drive Output PowerPower (Watts) (kiloWatts) 7,000 6,465 --- --- 2,158.0 1,384.0 1,225.0 2,015.0 The values listed above represent specified limits for the product and are subject to change. The data should be used for basic information only. Formal, controlled specifications may be obtained from CPI for use in equipment design. For information on this and other CPI MPP products, visit our website at: www.cpii.com, or contact: CPI Microwave Products Division, Eimac Operation,607 Hansen Way, Palo Alto, CA 94303 telephone : 1(800) 414-8823. fax : (650) 592-9988 | email : [email protected] CPI | 8974 / X-2159 4CW50,000J 8974 / X-2159