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Voltage - Triode (single) ·Triode

417A

Frame-grid single triode designed especially for low-noise intermediate-frequency amplification, providing high transconductance for sensitive receiver stages.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
9V
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 300 mA

Description

Frame-grid single triode designed especially for low-noise intermediate-frequency amplification.

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
9V
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9V - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN1PAP — Plate (Anode)

EIA source designation P; manufacturer verification pending

Unverified

EIA Base Connections, printed page 130, 9V

PIN3H—H — Heater

EIA source designation H; manufacturer verification pending

Unverified

EIA Base Connections, printed page 130, 9V

PIN4G1AG1 — Control Grid

EIA source designation G1; manufacturer verification pending

Unverified

EIA Base Connections, printed page 130, 9V

PIN5G1AG1 — Control Grid

EIA source designation G1; manufacturer verification pending

Unverified

EIA Base Connections, printed page 130, 9V

PIN6KAK — Cathode

EIA source designation K; manufacturer verification pending

Unverified

EIA Base Connections, printed page 130, 9V

PIN7G1AG1 — Control Grid

EIA source designation G1; manufacturer verification pending

Unverified

EIA Base Connections, printed page 130, 9V

PIN8G1AG1 — Control Grid

EIA chart transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9V

PIN9H—H — Heater

EIA chart transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9V

Section ratings

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
1850 Ω
Transconductance
0.02 S
Amplification factor
44
Max plate voltage
200 V
Max plate dissipation
4.5 W
Max cathode current
40 mA

Promoted fields mapped from printed maximum-rating and characteristic headings; additional published values preserved in parameter rows.

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

1965 Ericsson Longlife

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate supply voltage

    130 V

    ClassA

  • Grid supply voltage

    9 V

    ClassA

  • Cathode bias resistor

    360 Ohm

    ClassA

  • Plate current

    27 mA

    ClassA

  • Plate supply voltage

    150 V

    ClassA

  • Cathode bias resistor

    60 Ohm

    ClassA

  • Plate current

    25 mA

    ClassA

  • Transconductance minimum

    20000 uS

  • Transconductance maximum

    30000 uS

Characteristics

  • Transconductance

    27000 uS

    ClassA;Va=130V

  • Amplification factor

    44 ratio

    ClassA;Va=130V

  • Plate resistance

    1600 Ohm

    ClassA;Va=130V

  • Transconductance

    25000 uS

    ClassA;Va=150V

  • Amplification factor

    43 ratio

    ClassA;Va=150V

  • Plate resistance

    1700 Ohm

    ClassA;Va=150V

  • Equivalent noise resistance

    100 Ohm

Data set 02

1971 RCA HB3 Binder 3 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum plate voltage

    - to 200 V

  • Maximum plate dissipation

    - to 4.5 W

  • Maximum cathode current

    - to 38 mA

Characteristics

  • Plate resistance

    1700 Ω

  • Transconductance

    25000 µS

  • Amplification factor

    43

  • Plate supply voltage

    130 V

    ClassA

  • Plate supply voltage

    150 V

    ClassA

  • Amplification factor

    43

    ClassA

  • Plate resistance

    1600 Ω

    ClassA

  • Plate resistance

    1700 Ω

    ClassA

  • Transconductance

    27000 µS

    ClassA

  • Transconductance

    25000 µS

    ClassA

  • Plate current

    27 mA

    ClassA

  • Plate current

    25 mA

    ClassA

Capacitance

  • Plate to cathode and heater

    0.55 pF

Data set 03

2026 Western Electric 400s

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater Voltage

    6.3 volts

    Heater Voltage . 6.3 volts

  • Heater Current

    300 milliamperes

    Heater Current 300 milliamperes

  • Plate Voltage

    200 volts

    Plate Voltage- 200 volts

  • Cathode Current

    40 milliamperes

    Cathode Current- 40 milliamperes

  • Heater Cathode voltage

    55 volts

    Heater Cathode voltage- 55 volts

  • Bulb Temperature

    130 centigrade

    Bulb Temperature 130° centigrade

  • Plate Supply Voltage

    130 volts

    Plate Supply Voltage. 130 150 volts

  • Plate Current

    23 milliamperes

    Plate Current . 23.0 22.5 milliamperes

  • Plate Resistance

    1850 ohms

    Plate Resistance 1850 1700 ohms

  • Transconductance

    20000 micromhos

    Transconductance 20000 25000 micromhos

Other

  • Maximum Plate voltage

    200 volts

    Maximum Plate voltage 200 volts

  • Plate Dissipation

    -4.5 watts

    Plate Dissipation - 4.5 watts