TUBE 4CM500,000G / TH558 / RS 2078 SK / DB935

GENERAL DESCRIPTION


photo 4CM500,000G The 4CM500,000G / TH558 / RS 2078 SK / DB935 is a ceramic/metal, multiphase-cooled (water/vapor) power tetrode. This tube has a thoriated tungsten mesh filament and pyrolytic graphite grids which provide high-dissipation combined with low secondary emission characteristics.

Base coaxial contact rings are provided for the filament, grid, and screen terminals, and these terminals are cooled with forced air. The maximum anode dissipation rating is 500 kilowatts steady state, with multiphase cooling.
picture 4CM500,000G


TECHNICAL SPECIFICATIONS
ELECTRICAL
Filament
 Voltage (DC or AC)
 Current at 23.0 volts nominal
 Peak Maximum Filament Inrush Current at Turn-on
Thoriated Tungsten
23.0 Volts
500 Amperes
1000 Amperes
Amplification Factor, average Grid to Screen 4.4
Maximum Frequency of CW Ratings 50 MHz
Highest Useful Frequency With Reduced Ratings 110 MHz
Direct Interelectrode Capacitance (nominal values)
 Cg1k
 Cg2k
 Cpk
 Cg1g2
 Cg1p
 Cg2p

445 pF
40 pF
0.6 pF
750 pF
6.3 pF
100 pF
MECHANICAL
Maximum Overall Dimensions
 Length
 Diameter

25.7 in; 65.3 cm
12.6 in; 32.1 cm
Net Weight (approximate) 150 lbs; 70 kg
Operating Position Vertical, base down
Cooling Water & Forced Air
Maximum Operating Temperature:
 Envelope and Ceramic/Metal Seals

200°C
Specifications may change without notice

THIS TUBE IS USED IN THE FOLLOWING SHORTWAVE BROADCAST TRANSMITTERS
Manufacturer Transmitter specifications Power in kW
Ampegon TSW 2300D 300
Continental Electronics 420 B 500
420 C 500
Marconi B 6133 250
B 6127 500
B 6128 500
B 6128S 500
Kokusai Denki TA-3001 300
RIZ Transmitters OR 250 K-02/A 250
OR 300 K-02/A 300
OR 500 K-01/A 500
Telefunken S 4005 100
Thales TSW 2250 250
TSW 2300 300
Thomson TRE 2335 300
TRE 2352 500
TRE 2355 500
Thomson TSW 2250 D 250
TSW 2300 D 300


THIS TUBE IS AVAILABLE FROM
Manufacturer Rebuilder Distributor
Eimac Econco Richardson Electronics
Thales Kennetron
Xuguang



PRICE LEVEL (US$)
1 2 3 4 5 6
0 - 10 10 - 100 100 - 1000 1000 - 10,000 10,000 - 50,000 50,000 - 100,000