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Power - Beam (NOT sweep) (over 1000V 100W) ·BeamPower

4B38

Air-cooled beam-power tube designed for RF power service and Class-AB1 audio-frequency power-amplifier and modulator applications.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6.3 V / -

Description

The 4B38 is an air-cooled beam-power tube for RF power service and class-AB1 audio-frequency power-amplifier and modulator applications.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
-
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Beam Power

X-ray radiationInterelectrode capacitances
Transconductance
0.02 S
Max plate voltage
1250 V
Max plate dissipation
150 W

Published maximum ratings and characteristics audited; remaining numeric data retained densely in parameter table.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1971 NEC

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

  • Heater Voltage

    6.3 V

    Heater Voltage 6.3 Volts

  • Heater Current

    4.8 A

    Heater Current 4.8 Amps

  • Amplification Factor Grid No

    2

    Amplification Factor Grid No.2 s'm,"‘“__ T

  • to Grid No.l

    6

    to Grid No.l 6

  • Grid No.l to Plate

    1.5

    Grid No.l to Plate 1.5 unF

  • Input

    50

    Input 50 wuF

  • Output

    20

    Output 20 uuF

  • Heater to Cathode ~—mw

    25

    Heater to Cathode ~—mw- 25 puf

  • Transconductance

    20

    Transconductance . 20 millimhos

  • Maximum Frequency for Maximum Ratings

    10 MHz

    Maximum Frequency for Maximum Ratings - 10MHz/s FEy

  • Base;

    1

    Base; 1; Heater

  • Published value

    2

    2o Grid N,Y

  • Bottom Part - E3 [1]

    25

    Bottom Part - E325-2 4; Grid No.3 and

  • Bottom Part - E3 [2]

    -2

    Bottom Part - E325-2 4; Grid No.3 and

  • Bottom Part - E3 [3]

    4

    Bottom Part - E325-2 4; Grid No.3 and

  • Bottom Part - E3 [4]

    3

    Bottom Part - E325-2 4; Grid No.3 and

  • Published value

    53

    53 Heater

  • DC Plate Voltag

    1250

    DC Plate Voltag- 1250 Volts

  • DC Grid No [1]

    2 V

    DC Grid No.2 Voltage ———e—mmmm e 400 Volts

  • DC Grid No [2]

    400 V

    DC Grid No.2 Voltage ———e—mmmm e 400 Volts

  • Max. Signal DC Plate Current*

    600 A

    Max. Signal DC Plate Current* 600 mA

  • Max. Signal Flute Input*

    450

    Max. Signal Flute Input* 450 Watts

  • Plate Dissipation

    150 W

    Plate Dissipation 150 Watts

  • Peak Heater to Cathode Voltage +

    500 V

    Peak Heater to Cathode Voltage +500 Volts

  • DC Plate Voltuge [1]

    800

    DC Plate Voltuge - 800 1000 Volrs

  • DC Plate Voltuge [2]

    1000

    DC Plate Voltuge - 800 1000 Volrs

  • DC Grid No [1]

    2 V

    DC Grid No.2 Voltage 300 300 Volx.

  • DC Grid No [2]

    300 V

    DC Grid No.2 Voltage 300 300 Volx.

  • DC Grid No [3]

    300 V

    DC Grid No.2 Voltage 300 300 Volx.

  • DC Grid No.l Voltage -- = [1]

    50 V

    DC Grid No.l Voltage -- =50 ~50 Volt:s

  • DC Grid No.l Voltage -- = [2]

    50 V

    DC Grid No.l Voltage -- =50 ~50 Volt:s

  • Peak AF Grid No.l to Grid No.l Voltupge ——m—mcmmece [1]

    106

    Peak AF Grid No.l to Grid No.l Voltupge ——m—mcmmece 106 106G Vi

  • Peak AF Grid No.l to Grid No.l Voltupge ——m—mcmmece [2]

    106

    Peak AF Grid No.l to Grid No.l Voltupge ——m—mcmmece 106 106G Vi

  • Zero-Signal DC Plate Current [1]

    160 A

    Zero-Signal DC Plate Current 160 80 ma

  • Zero-Signal DC Plate Current [2]

    80 A

    Zero-Signal DC Plate Current 160 80 ma

  • Max. Signal DC Grid No [1]

    2 A

    Max. Signal DC Grid No.2 Current 80 70 mA

  • Max. Signal DC Grid No [2]

    80 A

    Max. Signal DC Grid No.2 Current 80 70 mA

  • Max. Signal DC Grid No [3]

    70 A

    Max. Signal DC Grid No.2 Current 80 70 mA

  • Effective Load Resistance (Plate to Plate) —me————e——-= [1]

    1900

    Effective Load Resistance (Plate to Plate) —me————e——-= 1900 2800 Chms

  • Effective Load Resistance (Plate to Plate) —me————e——-= [2]

    2800

    Effective Load Resistance (Plate to Plate) —me————e——-= 1900 2800 Chms

  • Plate Power Cutput (approx.) [1]

    380 W

    Plate Power Cutput (approx.) 380 450 Wat-o

  • Plate Power Cutput (approx.) [2]

    450 W

    Plate Power Cutput (approx.) 380 450 Wat-o

  • " Plate Voltage -—- -— [1]

    1000 V

    " Plate Voltage -—- -— 1000 V-0

  • " Plate Voltage -—- -— [2]

    0 V

    " Plate Voltage -—- -— 1000 V-0

  • DC Grid No

    2 V

    DC Grid No.2 Voltage Volts

  • Max. Signal Peak Plate Current ——

    1.3 A

    Max. Signal Peak Plate Current —— 1.3 Amps

  • Zero-Signal DC Plate Current [1]

    100 A

    Zero-Signal DC Plate Current -- 100 80

  • Zero-Signal DC Plate Current [2]

    80 A

    Zero-Signal DC Plate Current -- 100 80

  • Max. Signal DC Grid No [1]

    2 A

    Max. Signal DC Grid No.2 Current 80 70

  • Max. Signal DC Grid No [2]

    80 A

    Max. Signal DC Grid No.2 Current 80 70

  • Max. Signal DC Grid No [3]

    70 A

    Max. Signal DC Grid No.2 Current 80 70

  • Peak AF Cathode to Cathode Voltage [1]

    1200 V

    Peak AF Cathode to Cathode Voltage - 1200 1600 Volts

  • Peak AF Cathode to Cathode Voltage [2]

    1600 V

    Peak AF Cathode to Cathode Voltage - 1200 1600 Volts

  • Plate Power Output (approx.) [1]

    380 W

    Plate Power Output (approx.) 380 450 Watts

  • Plate Power Output (approx.) [2]

    450 W

    Plate Power Output (approx.) 380 450 Watts

  • Note; Peak Cathode to Grid No.l Voltage should never exceed +

    300 V

    Note; Peak Cathode to Grid No.l Voltage should never exceed +300 Volts.

  • PLATE CHARACTERISTICS (

    1

    PLATE CHARACTERISTICS (1)

  • DC PLATE CURRENT

    1 A

    DC PLATE CURRENT 1b(A)

  • PLATE CHARACTERISITCS (

    2

    PLATE CHARACTERISITCS (2)

  • DC GRID NO [1]

    2

    DC GRID NO.2 CURR:NT 1c2(mA)

  • DC GRID NO [2]

    1

    DC GRID NO.2 CURR:NT 1c2(mA)

  • GRID NO

    1

    GRID NO.1 VCOLTAGE i.~