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Voltage Pentode - Sharp Cutoff (single) ·Pentode

4HM6

Sharp-cutoff pentode designed for television IF, picture-IF, video, or VHF tuner amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
9PM
Socket code
B9A
Base pins
9
Nominal heater
4.2 V / 450 mA

Description

Frame-grid sharp-cutoff pentode for television IF amplifier service.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
9PM
Socket code
B9A
Base pins
9
Nominal heater voltage
4.2 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9PM - 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
Plate resistance
156000 Ω
Transconductance
0.0155 S
Max plate voltage
250 V
Max screen voltage
250 V
Max plate dissipation
2.5 W
Max screen dissipation
0.7 W
Max cathode current
25 mA

Published Class A1 characteristics and design-maximum ratings.

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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • TransconductancePublished

    15500 uS

Data set 02

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate voltage

    125 V

  • Screen-grid voltage

    125 V

  • Cathode bias resistor

    56 Ohm

  • Plate current

    13 mA

  • Screen-grid current

    3.2 mA

Characteristics

  • Plate resistance

    156000 Ohm

  • Transconductance

    15000 uS

  • Control-grid cutoff voltage

    -3 V

  • Hot input resistance

    13500 Ohm

Capacitance

  • Grid-to-plate capacitance

    0.024 pF

    Shielded

  • Input capacitance

    8.7 pF

    Shielded

  • Output capacitance

    3 pF

    Shielded

Data set 03

1965 Westinghouse Data Book

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Heater Voltage

    4.2 V

  • Heater Current

    450 mA

  • Plate Resistance

    156000 ohm

    RepresentativePublishedPoint

Other

  • Maximum Plate Voltage

    250 V

  • Maximum Plate Dissipation

    2.5 W

Data set 04

1966 Tung Sol Electronic Tubes 1 of 4

Published operating points and test conditions from this source.

SECTION 1

Pentode

Capacitance

  • GRID TO PLATE

    0.031 pF

    Capacitances | GRID TO PLATE 0.024 0.031 pf

Other

  • HEATER WARM-UP TIME

    11 s

    Average Characteristics | HEATER WARM-UP TIME 11 SECONDS

  • LIMITS OF SUPPLIED CURRENT

    450130 mA

    Average Characteristics | LIMITS OF SUPPLIED CURRENT 450130 MA.

  • PLATE VOL TAGE

    250 V

    Maximum Ratings | PLATE VOL TAGE 250 VOLTS

  • GRID

    250 V

    Maximum Ratings | GRID 2 SUPPLY VOLTAGE 250 VOLTS

  • NEGATIVE GRID

    50 V

    Maximum Ratings | NEGATIVE GRID 1 VOLTAGE 50 VOLTS

  • PLATE DISSIPATION

    2.5 W

    Maximum Ratings | PLATE DISSIPATION 2.5 WATTS

  • GRID

    125 V

    Maximum Ratings | GRID 2 DISSIPATION - UP TO 125 VOLTS 0.6 WATT

  • GRID

    0.6 W

    Maximum Ratings | GRID 2 DISSIPATION - UP TO 125 VOLTS 0.6 WATT

  • CATHODE-BIAS RESISTOR

    1 Mohm

    Maximum Ratings | CATHODE-BIAS RESISTOR 1 MEGOHM

  • FIXED BIAS

    0.25 Mohm

    Maximum Ratings | FIXED BIAS 0.25 MEGOHM

  • PLATE VOLTAGE

    125 V

    Maximum Ratings | PLATE VOLTAGE 125 VOLTS

  • GRID

    125 V

    Maximum Ratings | GRID 2 VOLTAGE 125 VOLTS

  • PLATE CURRENT

    13 mA

    Maximum Ratings | PLATE CURRENT 13 MA.

  • GRID

    3.2 mA

    Maximum Ratings | GRID 2 CURRENT 3.2 MA.

  • PLATE RESISTANCE

    0.156 Mohm

    Maximum Ratings | PLATE RESISTANCE 0.156 MEGOHM

  • HOT INPUT RESISTANCE A

    13 ohm

    Maximum Ratings | HOT INPUT RESISTANCE A 13.000 OHMS

  • HOT INPUT CAPACITANCE A

    7.4 pF

    Maximum Ratings | HOT INPUT CAPACITANCE A 7.4 pf

  • (GRID

    100 ΜMHOS

    Maximum Ratings | (GRID 1 VOLTAGE AT Gm = 100 µMHOS —3.0 VOLTS

  • (GRID

    3 V

    Maximum Ratings | (GRID 1 VOLTAGE AT Gm = 100 µMHOS —3.0 VOLTS

  • MEASURED AT dd MC/

    56 ohm

    Maximum Ratings | MEASURED AT dd MC/5 WITH UN BY PASSED 56 OHM CATHODE RESISTOR.

  • GRID q

    2 V

    Maximum Ratings | GRID q2 VOLTS

  • GRID q

    2 mA

    Maximum Ratings | GRID q2 MILLIAMPERES

Data set 05

1971 RCA HB3 Binder 4 of 7

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate supply voltage

    125 V

    ClassA1

  • Grid 2 supply voltage

    125 V

    ClassA1

  • Cathode resistor

    56 ohm

    ClassA1

  • Plate current

    13 mA

    ClassA1

  • Grid 2 current

    3.2 mA

    ClassA1

  • Grid 1 voltage for transconductance=100 uS

    -3 V

    ClassA1

  • Maximum negative grid 1 voltage

    50 V

  • Maximum fixed-bias grid circuit resistance

    0.25 Mohm

  • Maximum cathode-bias grid circuit resistance

    1 Mohm

Characteristic

  • Grid 1 to plate capacitance without external shield

    0.031 pF

  • Grid 1 to plate capacitance with external shield

    0.024 pF

  • Input capacitance

    8.7 pF

  • Output capacitance without external shield

    2.15 pF

  • Output capacitance with external shield

    3 pF

  • Heater warm-up time

    11 s

    ControlledWarmUp