Power - Triode (over 1000V 100W) ·Triode
Western Electric directly heated air-cooled transmitting triode for high-power Class C RF service. Roughly 400 W plate dissipation and 4 kV plate capability support substantial communications and broadcast transmitter output stages.
The Western Electric 357B is a directly heated air-cooled transmitting triode for high-power Class C RF service.
Medium-shell UX 4-contact
General specifications
Properties common to every published source and operating point.
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
1 physical section, each with unique specifications.
Section 1
Maximum usable cathode current is plate current plus grid current. Amplification factor bogey 30 at Ip=200 mA, Ep=2 kV.
Source-dependent data
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 01
Published operating points and test conditions from this source.
Maximum Plate Current
500 mA
Maximum Frequency
100 MHz
Typical Maximum Power Output
350 W
ClassC; RF; PlateModulated
Typical Plate Voltage
700 V
Typical Plate Current
500 mA
Data set 02
Published operating points and test conditions from this source.
Published value [1]
400 kV
400 watts, Maximum ratings of 4 kVdc and 0.5 ampere by a straight-line, high-voltage process assuring the same
Published value [2]
4 kV
400 watts, Maximum ratings of 4 kVdc and 0.5 ampere by a straight-line, high-voltage process assuring the same
Published value [3]
0.5 kV
400 watts, Maximum ratings of 4 kVdc and 0.5 ampere by a straight-line, high-voltage process assuring the same
Filament VOltage oot
10 V
Filament VOltage oot 10 volts
Filament Current at
10 V
Filament Current at 10 volts ....oooviiiviviiiieiniiiccrec
Fitament Resistance, Cold
0.12
Fitament Resistance, Cold 0.12 ohm
Maximum Usable Cathode Current ....ocvvcvveveeevecneeinieereeee,
2.5 A
Maximum Usable Cathode Current ....ocvvcvveveeevecneeinieereeee, 2.5 amperes
Signal D-C Plate Current*
0.5
Signal D-C Plate Current* .. 0.50 ampere
Signal Plate Input*
1100 W
Signal Plate Input* 1100 watts
Plate Dissipation® ..................................................................................................... sasesvenses
400 W
Plate Dissipation® ..................................................................................................... sasesvenses 400 watts
Peak A-F Grid-to-Grid Voltage [1]
490 V
Peak A-F Grid-to-Grid Voltage 490 520 343 volts
Peak A-F Grid-to-Grid Voltage [2]
520 V
Peak A-F Grid-to-Grid Voltage 490 520 343 volts
Peak A-F Grid-to-Grid Voltage [3]
343 V
Peak A-F Grid-to-Grid Voltage 490 520 343 volts
Zero Signal D-C Plate Current ........ et e s [1]
0.16
Zero Signal D-C Plate Current ........ et e s .. 0.160 0.120 0.120 ampere
Zero Signal D-C Plate Current ........ et e s [2]
0.12
Zero Signal D-C Plate Current ........ et e s .. 0.160 0.120 0.120 ampere
Zero Signal D-C Plate Current ........ et e s [3]
0.12
Zero Signal D-C Plate Current ........ et e s .. 0.160 0.120 0.120 ampere
Maximum Signal D-C Plate Current [1]
1 mA
Maximum Signal D-C Plate Current . . . 1.00 0.72 0.43 ampere
Maximum Signal D-C Plate Current [2]
0.72 mA
Maximum Signal D-C Plate Current . . . 1.00 0.72 0.43 ampere
Maximum Signal D-C Plate Current [3]
0.43 mA
Maximum Signal D-C Plate Current . . . 1.00 0.72 0.43 ampere
Effective Load Resistance, Plate-to-Plate ....... ...... re rte n e raseresaann [1]
4360 ohm
Effective Load Resistance, Plate-to-Plate ....... ...... re rte n e raseresaann 4360 11500 14700 ohms
Effective Load Resistance, Plate-to-Plate ....... ...... re rte n e raseresaann [2]
11500 ohm
Effective Load Resistance, Plate-to-Plate ....... ...... re rte n e raseresaann 4360 11500 14700 ohms
Effective Load Resistance, Plate-to-Plate ....... ...... re rte n e raseresaann [3]
14700 ohm
Effective Load Resistance, Plate-to-Plate ....... ...... re rte n e raseresaann 4360 11500 14700 ohms
Maximum Signal Driving Power, approximate [1]
50 mA
Maximum Signal Driving Power, approximate 50.0 35.0 13.3 watts
Maximum Signal Driving Power, approximate [2]
35 mA
Maximum Signal Driving Power, approximate 50.0 35.0 13.3 watts
Maximum Signal Driving Power, approximate [3]
13.3 mA
Maximum Signal Driving Power, approximate 50.0 35.0 13.3 watts
Maximum Signal Power Output [1]
1400 mA
Maximum Signal Power Output 1400 1840 850 watts
Maximum Signal Power Output [2]
1840 mA
Maximum Signal Power Output 1400 1840 850 watts
Maximum Signal Power Output [3]
850 mA
Maximum Signal Power Output 1400 1840 850 watts
D-C Plate Voltage
4000 V
D-C Plate Voltage 4000 volts
D-C Plate Current
0.275
D-C Plate Current ... 0.275 ampecere
Plate Input
550 W
Plate Input ... 550 watts
Plate Dissipation
400 W
Plate Dissipation 400 watts
Peak R-F Grid Voltage [1]
135 V
Peak R-F Grid Voltage 135 136 volts
Peak R-F Grid Voltage [2]
136 V
Peak R-F Grid Voltage 135 136 volts
D-C Plate Current [1]
0.26
D-C Plate Current .......... 0.260 0.150 amperc
D-C Plate Current [2]
0.15
D-C Plate Current .......... 0.260 0.150 amperc
D-C Gnd Current, approximate [1]
0.1 mA
D-C Gnd Current, approximate 0.100 0.001 ampere
D-C Gnd Current, approximate [2]
0.001 mA
D-C Gnd Current, approximate 0.100 0.001 ampere
Driving Power, approxXimatet ... e st e
25 mA
Driving Power, approxXimatet ... e st e 25 watts
Power Qulput, apprOXimale .....cecccimioiinmerninieririossisstmesteersesssnssnssonesssssssssesss [1]
175 mA
Power Qulput, apprOXimale .....cecccimioiinmerninieririossisstmesteersesssnssnssonesssssssssesss 175 190 watts
Power Qulput, apprOXimale .....cecccimioiinmerninieririossisstmesteersesssnssnssonesssssssssesss [2]
190 mA
Power Qulput, apprOXimale .....cecccimioiinmerninieririossisstmesteersesssnssnssonesssssssssesss 175 190 watts
D-C Plate Voltage
3000 V
D-C Plate Voltage 3000 volts
D-C Grid Voltage
-500 V
D-C Grid Voltage . -500 volts
D-C Plate Current
0.4
D-C Plate Current . 0.400 ampere
D-C Grid Current
0.1
D-C Grid Current . 0.100 ampere
Plate Dissipation
235 W
Plate Dissipation 235 watts
D-C Plate Voltage [1]
2000 V
D-C Plate Voltage ................................................................................................................ 2000 3000 3000 volts
D-C Plate Voltage [2]
3000 V
D-C Plate Voltage ................................................................................................................ 2000 3000 3000 volts
D-C Plate Voltage [3]
3000 V
D-C Plate Voltage ................................................................................................................ 2000 3000 3000 volts
D-C Grid Voltage [1]
-310 V
D-C Grid Voltage -310 ~320 =270 volts
D-C Grid Voltage [2]
320 V
D-C Grid Voltage -310 ~320 =270 volts
D-C Grid Voltage [3]
270 V
D-C Grid Voltage -310 ~320 =270 volts
Pcak R-F Grid Voltage [1]
535 V
Pcak R-F Grid Voltage 535 520 420 volts
Pcak R-F Grid Voltage [2]
520 V
Pcak R-F Grid Voltage 535 520 420 volts
Pcak R-F Grid Voltage [3]
420 V
Pcak R-F Grid Voltage 535 520 420 volts
D-C Plate Current [1]
0.39
D-C Plate Current 0.390 0.340 0.240 ampere
D-C Plate Current [2]
0.34
D-C Plate Current 0.390 0.340 0.240 ampere
D-C Plate Current [3]
0.24
D-C Plate Current 0.390 0.340 0.240 ampere
Driving Power, approximate [1]
35 mA
Driving Power, approximate ... 35 35 20 watts
Driving Power, approximate [2]
35 mA
Driving Power, approximate ... 35 35 20 watts
Driving Power, approximate [3]
20 mA
Driving Power, approximate ... 35 35 20 watts
D-C Grid Voltage =
500 V
D-C Grid Voltage =500 volts
D-C Plate Current
0.5
D-C Plate Current . 0.500 ampere
Plate Input
1800 W
Plate Input ... 1800 watts
D-C Plate VOltage oo ettt es e s st e e sp s sas e [1]
2000 V
D-C Plate VOltage oo ettt es e s st e e sp s sas e 2000 3500 volts
D-C Plate VOltage oo ettt es e s st e e sp s sas e [2]
3500 V
D-C Plate VOltage oo ettt es e s st e e sp s sas e 2000 3500 volts
D-C Gnd Voltage ..o [1]
-200 V
D-C Gnd Voltage ..o -200 -240 volts
D-C Gnd Voltage ..o [2]
-240 V
D-C Gnd Voltage ..o -200 -240 volts
Peak R-F Grid Voltage [1]
445 V
Peak R-F Grid Voltage 445 460 volts
Peak R-F Grid Voltage [2]
460 V
Peak R-F Grid Voltage 445 460 volts
D-C Plate Current [1]
0.5
D-C Plate Current ........... 0.500 0.450 ampere
D-C Plate Current [2]
0.45
D-C Plate Current ........... 0.500 0.450 ampere
D-C Grid Current, approximate [1]
0.085 mA
D-C Grid Current, approximate 0.085 0.070 ampere
D-C Grid Current, approximate [2]
0.07 mA
D-C Grid Current, approximate 0.085 0.070 ampere
Driving Power, approximate [1]
733 mA
Driving Power, approximate .......... . 733 30 watts
Driving Power, approximate [2]
30 mA
Driving Power, approximate .......... . 733 30 watts
+ At crest of audio-frequency cycle with modulation factor of
1
+ At crest of audio-frequency cycle with modulation factor of 1.0. )
affected. frequency above
40 MHz
affected. frequency above 40 megacycles, forced-air cooling is neces:
Frequency [1]
100 MHz
Frequency 100 125 150 megacycles sary. Satisfactory air cooling will be obtained from a blowr
Frequency [2]
125 MHz
Frequency 100 125 150 megacycles sary. Satisfactory air cooling will be obtained from a blowr
Frequency [3]
150 MHz
Frequency 100 125 150 megacycles sary. Satisfactory air cooling will be obtained from a blowr
”‘lt"d _plate voltage and from a
2
”‘lt"d _plate voltage and from a 2-inch diameter nozzle. The nozzle outlet should be
Clffisfltg input [1]
100 mA
Clffisfltg input 100 8s 70 per cent placed approximately 3 inches from the tube and directed
Clffisfltg input [2]
8 mA
Clffisfltg input 100 8s 70 per cent placed approximately 3 inches from the tube and directed
Clffisfltg input [3]
70 mA
Clffisfltg input 100 8s 70 per cent placed approximately 3 inches from the tube and directed
Clffisfltg input [4]
3 mA
Clffisfltg input 100 8s 70 per cent placed approximately 3 inches from the tube and directed
Data set 03
Published operating points and test conditions from this source.
GridPlateCapacitance
4.25 pF
Bogey
GridFilamentCapacitance
11.5 pF
Bogey
PlateFilamentCapacitance
2.5 pF
Bogey
Maximum DC Plate Current
500 mA
General maximum rating
Maximum DC Grid Current
100 mA
General maximum rating
MaximumPlateInputClassCTelegraphy
1800 W
ClassC; Telegraphy
MaximumSignalPowerOutputClassB
1840 W
ClassB; PushPull; TwoTubes