241B

Filamentary transmitting triode designed for radio-frequency power amplification and oscillator operation. Published service data emphasize transmitter duty, high plate loading, and useful RF output.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: GIANT3
Base pins: -
Nominal heater: 14 V / 6 A

Description

The Western Electric 241B is a triode listed in the supplied catalog table. It is an air-cooled transmitting type intended for RF power service.

Socket description

Giant 3-contact transmitting-tube base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: GIANT3
Base pins: -
Nominal heater voltage: 14 V
Nominal heater current: 6 A
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

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 1900 Ω
Transconductance: 0.0085 S
Amplification factor: 16
Max plate voltage: 3000 V
Max plate dissipation: 275 W
Max cathode current: 350 mA

Promoted fields mapped from published ratings/characteristics; additional published values preserved 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

1956 Western Electric Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

Maximum/Typical Power Output
150 W
Catalog-table value

Other

Maximum Plate Voltage
3000 V
Catalog-table value
Maximum Plate Dissipation
275 W
Catalog-table value

Data set 02

1971 Machlette Laboratories

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

Maximum ratings of [1]
3 kV
Maximum ratings of 3 kVdc and 350 milliamperes apply at hausted by a straight-line, high-voltage process assuring the
Maximum ratings of [2]
350 kV
Maximum ratings of 3 kVdc and 350 milliamperes apply at hausted by a straight-line, high-voltage process assuring the
missible with plate voltage reduced to
1 kV
missible with plate voltage reduced to 1 kVdc. and super-voltage x-ray tubes.
Filament Current at [1]
14 V
Filament Current at 14 volts 6 amperes
Filament Current at [2]
6 V
Filament Current at 14 volts 6 amperes
Amplification Factor
16
Amplification Factor ............... 16
Grid-Plate Transconductance
8500
Grid-Plate Transconductance 8500 ubfhos
Direct Plate Voltage
3600 V
Direct Plate Voltage 3600 volts
Direct Plate Current
350 A
Direct Plate Current .. 350 milliamperes
Plate Dissipation
275 W
Plate Dissipation ...... 275 watts
Direct Grid Current
75 A
Direct Grid Current 75 milliamperes
Frequency e,
7.5 MHz
Frequency e, 7.5 megacycles
Direct Plate Current [1]
170 A
Direct Plate Current 170 200 milliamperes
Direct Plate Current [2]
200 A
Direct Plate Current 170 200 milliamperes
Published value [1]
103 ohm
1,03(! Impedance .. 5000 3000 ohms
Published value [2]
5000 ohm
1,03(! Impedance .. 5000 3000 ohms
Published value [3]
3000 ohm
1,03(! Impedance .. 5000 3000 ohms
Plate Dissipation
175 W
Plate Dissipation 175 watts
Load IMpedance ...o.ooiiiesecaeeieestee e
8000 ohm
Load IMpedance ...o.ooiiiesecaeeieestee e 8000 ohms
Peak POWer OUIPUL oot ettt et eeteeneeterese et e rseeeeaenreanee
200 W
Peak POWer OUIPUL oot ettt et eeteeneeterese et e rseeeeaenreanee 200 watts
Plate Dissipation ..o [1]
250 W
Plate Dissipation ..o 250 200 watts
Plate Dissipation ..o [2]
200 W
Plate Dissipation ..o 250 200 watts
Load Resistance (plate-io-plate) [1]
8000 ohm
Load Resistance (plate-io-plate) . 8000 5900 ohms
Load Resistance (plate-io-plate) [2]
5900 ohm
Load Resistance (plate-io-plate) . 8000 5900 ohms
Load Resistance (per tube) [1]
2000 ohm
Load Resistance (per tube) . 2000 1475 ohms
Load Resistance (per tube) [2]
1475 ohm
Load Resistance (per tube) . 2000 1475 ohms
Recommended Power for driving SIage ..o [1]
50 W
Recommended Power for driving SIage ..o 50 50 watts
Recommended Power for driving SIage ..o [2]
50 W
Recommended Power for driving SIage ..o 50 50 watts
Direct Plate Current [1]
300 A
Direct Plate Current 300 270 milliamperes
Direct Plate Current [2]
270 A
Direct Plate Current 300 270 milliamperes
Plate Dissipation [1]
275 W
Plate Dissipation 275 275 watts
Plate Dissipation [2]
275 W
Plate Dissipation 275 275 watts
Direct Plate Current [1]
300 A
Direct Plate Current . 300 300 milliamperes
Direct Plate Current [2]
300 A
Direct Plate Current . 300 300 milliamperes
Direct Grid Current [1]
75 A
Direct Grid Current ... 75 75 milliamperes
Direct Grid Current [2]
75 A
Direct Grid Current ... 75 75 milliamperes
Nominal Cartier Power Qutput for use with [1]
100
Nominal Cartier Power Qutput for use with 100% modulation ... 300 200 walts
Nominal Cartier Power Qutput for use with [2]
300
Nominal Cartier Power Qutput for use with 100% modulation ... 300 200 walts
Nominal Cartier Power Qutput for use with [3]
200
Nominal Cartier Power Qutput for use with 100% modulation ... 300 200 walts
voltage for frequencies between [1]
7.5 MHz
voltage for frequencies between 7.5 and 22,5 megacycles
voltage for frequencies between [2]
225 MHz
voltage for frequencies between 7.5 and 22,5 megacycles

Data set 03

2026 Western Electric 200s

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

Filament voltage
14 volt
Filament voltage 14 volts
Average thermionic emission
4 amperes
Average thermionic emission 4 amperes
Average Characteristics at
2000 volts
Average Characteristics at 2000 volts direct plate potential and minus 90 volts grid bias.
Amplification factor
16
Amplification factor 16
Plate resistance
1900 ohms
Plate resistance 1900 ohms
Grid to plate transconductance
8500 micromhos
Grid to plate transconductance 8500 micromhos
Direct plate voltage
1500 volt
Direct plate voltage .1500 1250 volts
Grid bias
-5 volts
Grid bias . - 5 8 -40 volts
Direct plate current
170 milliamperes
Direct plate current . 170 200 milliamperes
Plate dissipation
250 watts
Plate dissipation . 250 250 watts
Load impedance
5000 ohms
Load impedance .5000 3000 ohms
Undistorted output
50 watts
Undistorted output . 50 40 watts
Plate dissipation
175 watts
Plate dissipation 175 watts
Load impedance
8000 ohms
Load impedance 8000 ohms
Peak power output
200 watts
Peak power output 200 watts
Plate dissipation
275 watts
Plate dissipation 275 200 watts
Load resistance plate-to-plate
8000 ohms
Load resistance plate-to-plate 8000 5900 ohms
Load resistance per tube
2000 ohms
Load resistance per tube 2000 1475 ohms
Direct plate current
200 milliamperes
Direct plate current 200 270 milliamperes
Plate dissipation
275 watts
Plate dissipation 275 275 watts
Grid bias
-120 volts
Grid bias —120 — 90 volts
Direct plate current
300 milliamperes
Direct plate current 300 300 milliamperes
Grid bias
-185 volts
Grid bias —185 to —250 —150 to —200 volts
Nominal power output
400 watts
Nominal power output 400 300 watts
fuse or circuit breaker should remove the plate voltage if the plate current exceeds
450 volt
fuse or circuit breaker should remove the plate voltage if the plate current exceeds 450 milliamperes.
circuit, reduced plate voltage or a series resistance of
1000 volt
circuit, reduced plate voltage or a series resistance of 1000 to 5000 ohms in the plate circuit should
A
5 volt
A 5% decrease in filament voltage reduces the thermionic emission approximately 25%. Either
resistance of
30 ohms
resistance of 30 to 40 ohms of ten watt rating is suitable.
voltages off,
30 volt
voltages off, 30% above normal voltage for 10 minutes followed by a longer period at normal
culated on the basis of
5
culated on the basis of 5% second harmonic distortion.
An audio voltage is superimposed on the grid driving voltage to modulate the signal
100 volt
An audio voltage is superimposed on the grid driving voltage to modulate the signal 100%.
of the plate voltage. For complete or
100 volt
of the plate voltage. For complete or 100% modulation, the plate voltage varies from zero
fourth of the peak power output under
100 volt
fourth of the peak power output under 100% modulation. In this case, since the plate voltage
frequency limit of
22.5 megacycles
frequency limit of 22.5 megacycles and for frequencies between these two limits the plate voltage

Other

Maximum direct plate voltage
3000 volt
Maximum direct plate voltage 3000 volts
Maximum direct plate current
350 milliamperes
Maximum direct plate current 350 milliamperes
Maximum plate dissipation
275 watts
Maximum plate dissipation 275 watts
Maximum direct grid current
75 milliamperes
Maximum direct grid current 75 milliamperes
Maximum r-f grid current
5 amperes
Maximum r-f grid current 5 amperes
Maximum frequency for the above ratings
7.5 megacycles
Maximum frequency for the above ratings.. . 7.5 megacycles
Maximum plate voltage for upper frequency l i m i t o f
2 volt
Maximum plate voltage for upper frequency l i m i t o f 2 2 . 5 M c 1000 volts
Maximum plate voltage for frequencies between
7.5 volt
Maximum plate voltage for frequencies between 7.5 and 22.5 Mc in
Direct plate voltage
3000 volt
Direct plate voltage 3000 volts (Max.)
Direct plate voltage
2000 volt
Direct plate voltage 2000 (Max.) 1500 volts
Approximate maximum output
650 watts
Approximate maximum output 650 500 watts
Direct plate voltage
2000 volt
Direct plate voltage 2000 (Max.) 1300 volts
Direct plate voltage
1500 volt
Direct plate voltage 1500 (Max.)