Product Description

Vt4cx250f/fs electronic tube is a side heated oxide cathode with coaxial cylinder structure and forced air-cooled cermet quadrupole. The maximum anode dissipation power is 250W. It is suitable for single sideband communication, radio and television and other ultrashort wave radio equipment for power amplification, voltage amplification, frequency modulation and frequency doubling. It can be interchanged with 4cx250fg electronic tubes produced by eimac company of the United States.

Specifications︰ 1、 Characteristic parameters
Hot wire voltage 26.5V Hot wire current 0.45～0.62A
transconductance 10mA/V Amplification factor five point two
Inter electrode capacitance (cathode grounding) input 14.2～19pF
output 5～6.5pF
Cross road 0.07pF
weight 140g Installation method arbitrarily
Maximum height 66mm Maximum outside diameter 42mm
Cooling mode Forced air cooling Maximum operating frequency 500MHz
Maximum air volume 0.113 m3/min Pipe socket Eimac SK-600A
Maximum operating temperature at anode and seal 250℃
2、 Limit operating value
Allowable working deviation of filament voltage 25.18～27.8V
Maximum anode DC voltage 2000V Maximum two grid DC voltage 400V
Maximum grid DC voltage - 250V Maximum anode average current 250mA
Maximum anode dissipation power 250W Maximum two grid dissipation power 12W
Highest grid dissipation power 2W Minimum preheating time of anode 3min
III Typical operating state audio amplifier or modulator class Ab1 (dual)
DC anode voltage 1000V 1500V 2000V
DC secondary grid voltage 350V 350V 350V
DC grid voltage - 55V - 55V - 55V
No signal anode DC current 200mA 200mA 200mA
Maximum signal anode DC current 500mA 500mA 500mA
Maximum signal second grid DC current 20mA 16mA 10mA
Maximum signal grid DC current 0 0 0
Maximum audio gate voltage 50V 50V 50V
Maximum excitation power 0 0 0
Anode input power 500W 750W 1000W
Anode output power 240W 430W 600W
Anode load resistance 3500Ω 6200Ω 9500Ω

Advantages︰ 1、 Characteristic parameters
Hot wire voltage 26.5V Hot wire current 0.45～0.62A
transconductance 10mA/V Amplification factor five point two
Inter electrode capacitance (cathode grounding) input 14.2～19pF
output 5～6.5pF
Cross road 0.07pF
weight 140g Installation method arbitrarily
Maximum height 66mm Maximum outside diameter 42mm
Cooling mode Forced air cooling Maximum operating frequency 500MHz
Maximum air volume 0.113 m3/min Pipe socket Eimac SK-600A
Maximum operating temperature at anode and seal 250℃
2、 Limit operating value
Allowable working deviation of filament voltage 25.18～27.8V
Maximum anode DC voltage 2000V Maximum two grid DC voltage 400V
Maximum grid DC voltage - 250V Maximum anode average current 250mA
Maximum anode dissipation power 250W Maximum two grid dissipation power 12W
Highest grid dissipation power 2W Minimum preheating time of anode 3min
III Typical operating state audio amplifier or modulator class Ab1 (dual)
DC anode voltage 1000V 1500V 2000V
DC secondary grid voltage 350V 350V 350V
DC grid voltage - 55V - 55V - 55V
No signal anode DC current 200mA 200mA 200mA
Maximum signal anode DC current 500mA 500mA 500mA
Maximum signal second grid DC current 20mA 16mA 10mA
Maximum signal grid DC current 0 0 0
Maximum audio gate voltage 50V 50V 50V
Maximum excitation power 0 0 0
Anode input power 500W 750W 1000W
Anode output power 240W 430W 600W
Anode load resistance 3500Ω 6200Ω 9500Ω