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Power - Triode Single (under 10W) ·Triode

7233

Very-low-mu power triode specifically designed as a series pass tube in regulated power supplies, with 8-watt plate dissipation.

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

Description

Very-low-mu power triode specifically designed as a series pass tube in regulated power supplies.

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
9FR
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
1 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9FR - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN1Base Pin—P — Plate (Anode)

Original chart label: P; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

PIN2Base Pin—G1 — Control Grid

Original chart label: G1; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

PIN3Base Pin—P — Plate (Anode)

Original chart label: P; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

PIN4Base Pin—H — Heater

Original chart label: H; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

PIN5Base Pin—H — Heater

Original chart label: H; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

PIN6Base Pin—P — Plate (Anode)

Original chart label: P; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

PIN7Base Pin—G1 — Control Grid

Original chart label: G1; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

PIN8Base Pin—K — Cathode

Original chart label: K; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

PIN9Base Pin—P — Plate (Anode)

Original chart label: P; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FR

Section ratings

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
230 Ω
Transconductance
0.0175 S
Amplification factor
4
Max plate voltage
330 V
Max plate dissipation
8 W
Max cathode current
150 mA

Series-regulator absolute maxima and average triode characteristics promoted.

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

1960 Mazda

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum Positive Grid Voltage

    0 V

  • Maximum Negative Grid Voltage

    -135 V

  • Maximum Heater Cathode Voltage

    300 V

  • TypicalPlateSupplyVoltage

    50 V

  • Cathode Bias Resistance

    22 ohm

  • Typical Plate Current

    120 mA

Data set 02

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate Supply Voltage

    250 V

    SeriesRegulator

  • Plate Voltage

    125 V

    SeriesRegulator

  • Cathode Bias Resistor

    22 ohm

    SeriesRegulator

  • Plate Current

    120 mA

    SeriesRegulator