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Power - Pentode (NOT beam) (over 1000V 100W) ·Pentode

P250A

Naturally air-cooled power pentode for RF power amplification, oscillator, modulator, and suppressor-grid-modulated service to approximately 25 MHz. Designed for versatile transmitting applications.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
12 V / 11 A

Description

The P250A is a naturally air-cooled power pentode for RF power-amplifier, oscillator, modulator, and suppressor-grid-modulated service at frequencies up to about 25 MHz.

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
12 V
Nominal heater current
11 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

Pentode

X-ray radiationInterelectrode capacitances
Transconductance
0.051 S
Amplification factor
6.5
Max plate voltage
3000 V
Max plate dissipation
420 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

Pentode

Other

  • Power Anplifier, OUscillator, Modulator, or Grid No

    3 W

    Power Anplifier, OUscillator, Modulator, or Grid No.3

  • Voltage ovvevecensacrassvsannnasanes

    12 V

    Voltage ovvevecensacrassvsannnasanes 12 Velts

  • Current (at nominal voltage)

    8.5 V

    Current (at nominal voltage) ....... - 8.5 Amps

  • Current (ot nominal voltage) eeeecee

    17 V

    Current (ot nominal voltage) eeeecee 17

  • Amplification Factor, Grid No.l to Grid Neo.)

    6.5

    Amplification Factor, Grid No.l to Grid Neo.) . 6.5

  • Grid No [1]

    1

    Grid No.1l to Plate c.veverveceecaans ' 0.16

  • Grid No [2]

    0.16

    Grid No.1l to Plate c.veverveceecaans ' 0.16

  • Frequency for max. Ratings .eeieeveegenns

    25

    Frequency for max. Ratings .eeieeveegenns 25

  • Published value [1]

    1

    1: Grid No.2 G - 5: Filament

  • Published value [2]

    2

    1: Grid No.2 G - 5: Filament

  • Published value [3]

    5

    1: Grid No.2 G - 5: Filament

  • Published value [1]

    2

    2: Filament Coumon Point _3 6: Grid No.l

  • Published value [2]

    3

    2: Filament Coumon Point _3 6: Grid No.l

  • Published value [3]

    6

    2: Filament Coumon Point _3 6: Grid No.l

  • G3: Grid No

    3

    G3: Grid No.3(upper base)

  • Published value [1]

    3

    3: Grid No.3

  • Published value [2]

    3

    3: Grid No.3

  • Published value

    4

    4: Filament

  • Maximum Upper Base Temperature coecees sovecesssse

    180

    Maximum Upper Base Temperature coecees sovecesssse 180°¢C

  • DC Plate Voltage ceveeeeveoanssarsessossecasscssnsess

    3000 V

    DC Plate Voltage ceveeeeveoanssarsessossecasscssnsess 3000 Volts

  • DC Grid No [1]

    3 V

    DC Grid No.3 Voltage ..civeeecsvresesscossasasssaeceass 100 Volts

  • DC Grid No [2]

    100 V

    DC Grid No.3 Voltage ..civeeecsvresesscossasasssaeceass 100 Volts

  • DC Grid No [1]

    2 V

    DC Grid No.2 Voltage covvereiesevveencecnnscncscnaaas 000 Volts

  • DC Grid No [2]

    0 V

    DC Grid No.2 Voltage covvereiesevveencecnnscncscnaaas 000 Volts

  • Voxe=Xrenal D Plate current (nobe

    1 A

    Voxe=Xrenal D Plate current (nobe 1) vuteee vevneens Ho A

  • Max.-Signal Plate Input (note [1]

    1

    Max.-Signal Plate Input (note 1) seeeeevsereceaeas.. 1000 Watts

  • Max.-Signal Plate Input (note [2]

    1000

    Max.-Signal Plate Input (note 1) seeeeevsereceaeas.. 1000 Watts

  • Plate Dissipation {(note [1]

    1 W

    Plate Dissipation {(note 1) tieeereeeecaerveseiecasas 420 Watts

  • Plate Dissipation {(note [2]

    420 W

    Plate Dissipation {(note 1) tieeereeeecaerveseiecasas 420 Watts

  • Grid No [1]

    2 W

    Grid No.2 Dissipation (note 1) sevevieviosnsneeesass TO Watts

  • Grid No [2]

    1 W

    Grid No.2 Dissipation (note 1) sevevieviosnsneeesass TO Watts

  • DC Grid No [1]

    3

    DC Grid No.3 Voltlame .. iieteeoeeraneissoansesanea O 0 Volts

  • DC Grid No [2]

    0

    DC Grid No.3 Voltlame .. iieteeoeeraneissoansesanea O 0 Volts

  • DC Grid No

    2 V

    DC Grid No.2 Voltage ......,

  • DO Grid No.l Voltage c.ieiiieeneiticencssenoncesnee = [1]

    70 V

    DO Grid No.l Voltage c.ieiiieeneiticencssenoncesnee =70 -70 Volts

  • DO Grid No.l Voltage c.ieiiieeneiticencssenoncesnee = [2]

    -70 V

    DO Grid No.l Voltage c.ieiiieeneiticencssenoncesnee =70 -70 Volts

  • Peak AF Grid No.l-to-Grid No.l Voltage ...c.eee [1]

    210 V

    Peak AF Grid No.l-to-Grid No.l Voltage ...c.eee. 210 200 Volts

  • Peak AF Grid No.l-to-Grid No.l Voltage ...c.eee [2]

    200 V

    Peak AF Grid No.l-to-Grid No.l Voltage ...c.eee. 210 200 Volts

  • Loro= [1]

    3 A

    Loro=3ignal DO Plate Current oevieeveecvencasaas 160 130 mA

  • Loro= [2]

    160 A

    Loro=3ignal DO Plate Current oevieeveecvencasaas 160 130 mA

  • Loro= [3]

    130 A

    Loro=3ignal DO Plate Current oevieeveecvencasaas 160 130 mA

  • Max.-Signal DC Plate Current ..eecesssecesesssss [1]

    800 A

    Max.-Signal DC Plate Current ..eecesssecesesssss 800 800

  • Max.-Signal DC Plate Current ..eecesssecesesssss [2]

    800 A

    Max.-Signal DC Plate Current ..eecesssecesesssss 800 800

  • lero-Signul DC Grid No [1]

    2 A

    lero-Signul DC Grid No.2 Currentl ...cvvececonans 4

  • lero-Signul DC Grid No [2]

    4 A

    lero-Signul DC Grid No.2 Currentl ...cvvececonans 4

  • Max.-Signal DC Grid No [1]

    2 A

    Max.-Signal DC Grid No.2 Current (approx.) ..... 25 mA

  • Max.-Signal DC Grid No [2]

    25 A

    Max.-Signal DC Grid No.2 Current (approx.) ..... 25 mA

  • Max.-Signal DC Grid No.l Current (approx.) « [1]

    21 A

    Max.-Signal DC Grid No.l Current (approx.) «.... 21 17 mA

  • Max.-Signal DC Grid No.l Current (approx.) « [2]

    17 A

    Max.-Signal DC Grid No.l Current (approx.) «.... 21 17 mA

  • Effective Load Resistance (Plate-to-Plate) [1]

    5080

    Effective Load Resistance (Plate-to-Plate) ..... 5080 6400 Ohms

  • Effective Load Resistance (Plate-to-Plate) [2]

    6400

    Effective Load Resistance (Plate-to-Plate) ..... 5080 6400 Ohms

  • Max.-Signal Driving Power (approx.) ....e..eeee [1]

    2.1 W

    Max.-Signal Driving Power (approx.) ....e..eeee. 2.1 1.6 Watts

  • Max.-Signal Driving Power (approx.) ....e..eeee [2]

    1.6 W

    Max.-Signal Driving Power (approx.) ....e..eeee. 2.1 1.6 Watts

  • Max.-Signal Power Output (approx.) « [1]

    1000 W

    Max.-Signal Power Output (approx.) «............ 1000 1200 Watts

  • Max.-Signal Power Output (approx.) « [2]

    1200 W

    Max.-Signal Power Output (approx.) «............ 1000 1200 Watts

  • Grid No

    3 W

    Grid No.3 Modulated RF Power Amplifier - Class C Telephony

  • DC Grid No [1]

    2

    DC Grid No.2 VOltiage eeeeeeceseseccascanssecenas 600 Volts

  • DC Grid No [2]

    600

    DC Grid No.2 VOltiage eeeeeeceseseccascanssecenas 600 Volts

  • DC Grid No.l Volbtage ceeevereeeveccnasssossnecnees =

    400

    DC Grid No.l Volbtage ceeevereeeveccnasssossnecnees =400 Volts

  • DC Plate CUTEENt o eeivsseovssesvasasreasaasossaea

    250

    DC Plate CUTEENt o eeivsseovssesvasasreasaasossaea 250 mA

  • DC Grid No.l Current ... ceeseeseive cossneccoscace

    40 A

    DC Grid No.l Current ... ceeseeseive cossneccoscace 40 mA

  • Plate Dissipation ceeeeeiesseesacreonnonessaaees

    420 W

    Plate Dissipation ceeeeeiesseesacreonnonessaaees 420 Watts

  • Please refer to *he "grid No

    3

    Please refer to *he "grid No.3 modulated characteristics,”

  • I Plate Voltuge o4 e s e o

    3000

    I Plate Voltuge o4 e s e o 3000

  • x urid No [1]

    2 V

    x urid No.2 Voltage 600

  • x urid No [2]

    600 V

    x urid No.2 Voltage 600

  • S Grid No.l Voltage ~

    -100 V

    S Grid No.l Voltage ~--100

  • "Plate Current

    500 A

    "Plate Current 500 &

  • ne Grid No.l Current .,

    10 A

    ne Grid No.l Current ., 10 mA

  • Plate Input

    1500

    Plate Input 1500 Watts

  • Plate Dissipation

    420 W

    Plate Dissipation .... 420 Wattls

  • DC Plate Voltage [1]

    2000 V

    DC Plate Voltage ... 2000 3000 Volts

  • DC Plate Voltage [2]

    3000 V

    DC Plate Voltage ... 2000 3000 Volts

  • DU Grid Noo3 Voltage [1]

    0 V

    DU Grid Noo3 Voltage . 0O 0 Voltus

  • DU Grid Noo3 Voltage [2]

    0 V

    DU Grid Noo3 Voltage . 0O 0 Voltus

  • DC Grid No [1]

    2

    DC Grid No.2 Voltuge . 0 500 Volts

  • DC Grid No [2]

    0

    DC Grid No.2 Voltuge . 0 500 Volts

  • DC Grid No [3]

    500

    DC Grid No.2 Voltuge . 0 500 Volts

  • DC Gr id No. I Voltage [1]

    -200 V

    DC Gr id No. I Voltage . -200 =200 Volts

  • DC Gr id No. I Voltage [2]

    200 V

    DC Gr id No. I Voltage . -200 =200 Volts

  • Peak RF Grid No.l Voltage [1]

    300 V

    Peak RF Grid No.l Voltage .... 300 300 Volts

  • Peak RF Grid No.l Voltage [2]

    300 V

    Peak RF Grid No.l Voltage .... 300 300 Volts

  • D Plate Current s e o & [1]

    0 mA

    D Plate Current s e o &0 e e o s 00 0 500 130 mA

  • D Plate Current s e o & [2]

    0 mA

    D Plate Current s e o &0 e e o s 00 0 500 130 mA

  • D Plate Current s e o & [3]

    0 mA

    D Plate Current s e o &0 e e o s 00 0 500 130 mA

  • D Plate Current s e o & [4]

    500 A

    D Plate Current s e o &0 e e o s 00 0 500 130 mA

  • D Plate Current s e o & [5]

    130 A

    D Plate Current s e o &0 e e o s 00 0 500 130 mA

  • Power Ontput (approx.) * o [1]

    0 W

    Power Ontput (approx.) * o 0 00 00 « 200 710 1050 Wit

  • Power Ontput (approx.) * o [2]

    0 W

    Power Ontput (approx.) * o 0 00 00 « 200 710 1050 Wit

  • Power Ontput (approx.) * o [3]

    0 W

    Power Ontput (approx.) * o 0 00 00 « 200 710 1050 Wit

  • Power Ontput (approx.) * o [4]

    200 W

    Power Ontput (approx.) * o 0 00 00 « 200 710 1050 Wit

  • Power Ontput (approx.) * o [5]

    710 W

    Power Ontput (approx.) * o 0 00 00 « 200 710 1050 Wit

  • Power Ontput (approx.) * o [6]

    1050 W

    Power Ontput (approx.) * o 0 00 00 « 200 710 1050 Wit

  • Load FPower Output (approx.) (note [1]

    2 W

    Load FPower Output (approx.) (note 2) o0 6H3i) 95 Watt s,

  • Load FPower Output (approx.) (note [2]

    6 W

    Load FPower Output (approx.) (note 2) o0 6H3i) 95 Watt s,

  • Load FPower Output (approx.) (note [3]

    95 W

    Load FPower Output (approx.) (note 2) o0 6H3i) 95 Watt s,

  • ot e Vidliie

    1 W

    ot e Vidliie 1= reduced by Jdriv Ny power for o=cijlator.

  • = FILAMENT VOLTAGE (E£)=

    12 V

    = FILAMENT VOLTAGE (E£)= 12Vac

  • = DC PLATE VOLTAGE=

    2000 V

    = DC PLATE VOLTAGE=2000vdc

  • & T DC GRID NO [1]

    2 V

    & T DC GRID NO.2 VOLTAGE (£cc2) =1000Vvde I