The Eimac 4CX250B/M is a ceramic/metal,

forced-air cooled external-anode tetrode with a

maximum anode dissipation rating of 250 Watts.

The 4CX250B/M is intended for use in applica-

tions where tight control of electrical specifica-

tions is required and replaces the 4CX250B in

all applications. This tube utilizes a ruggedized

internal structure and utilizes a welded anode cap

for improved reliability.

RADIAL BEAM POWER TETRODE

4CX250B/M

7203A

ChARACTERISTICS

1

CPI

CPI |

|

RADIAL BEAM POWER TETRODE 4CX250B/M / 7203A

4CW50,000J

ELECTRICAL

Cathode: Oxide coated, Unipotential

Filament Voltage

Current at 6.0 Volts

6.0± 0.3 V

2.6 A

Direct Interelectrode Capacitances (grounded cathode)

2

Cin

15.7 pF

Cout

4.5 pF

Cgp

0.04 pF

Amplification Factor, Average (screen-grid)

5

Frequency of Maximum Ratings (CW)

500 MHz

MECHANICAL:

Overall Dimensions:

Length

2.46 in; 62.5 mm

Diameter

1.64 in; 41.7 mm

Weight (approx.)

4 oz; 113 gm

Operating Postition

Any

Maximum Operating Temperature:

Ceramic/Metal Seals & Envelope

250° C

Anode Core

250° C

Cooling

Forced Air

Base

Special, 9-pin Jedec-B8-236

Recommended Air System Socket

SK-600 Series

Recommended Air Chimney

SK-606

1

Characteristics and operating values are based upon performance tests. These figures may change without notice as the result of additional data or product refinement.

CPI MPP, Eimac Operation should be consulted before using this information for final equipment design.

2

Capacitance values are for a cold tube as measured in a special shielded fixture in accordance with Electronic Industries Association Standard RS-191.

RANGE VALUES FOR EQUIPMENT DESIGN

Min.

Filament Current @ 6.0 Volts

Cathode Warm-up Time

Interelectrode Capacitance

1

(grounded cathode circuit)

Cin

Cout

Cgp

Interelectrode Capacitance

1

(grounded grid circuit)

Cin

Cout

Cpk

1

Nom.

--

60

--

--

--

13.0

--

0.01

Max.

2.9

--

17.2

5.0

0.06

--

5.0

--

Amperes

Seconds

pF

pF

pF

pF

pF

pF

2.3

30

14.2

4.0

--

--

4.0

--

Capacitance values are for a cold tube as measured in a shielded fixture in accordance with Electronic Industries Assocation Standard RS-191.

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 products, visit our website at:

www.cpii.com,

or contact: CPI MPP, Eimac Operation, 607 Hansen Way, Palo Alto, CA 94303

telephone

:

1(800) 414-8823.

fax

:

(650) 592-9988 |

email

:

powergrid@cpii.com

July 2011

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