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Power - Triode ·Triode-Triode

ECC99

Power-capable triode intended for amplifier or driver service. Manufacturer data support moderate-current operation and useful dissipation, but do not justify assignment to the large transmitting or specialized regulator families.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
-
Base pins
9
Nominal heater
6.3 V / 800 mA

Description

The source identifies this device as ECC99 R. F. double triode.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
800 mA
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

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
2300 Ω
Transconductance
0.0095 S
Amplification factor
22
Max plate voltage
400 V
Max plate dissipation
5 W
Max cathode current
60 mA

Authoritative title inside ECC899.pdf is ECC99; filename is retained only as provenance. Recommended uses include headphone amplifier output stages and small push-pull triode amplifiers.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
2300 Ω
Transconductance
0.0095 S
Amplification factor
22
Max plate voltage
400 V
Max plate dissipation
5 W
Max cathode current
60 mA

Second physical triode section; added to align double-triode structure with SectionCount=2.

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

199X JJ

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Typical Plate Voltage

    150 V

  • TypicalGridVoltage

    -4 V

  • Typical Plate Current

    18 mA

Characteristic

  • Grid Cathode Capacitance

    5.8 pF

  • Plate Capacitance

    0.91 pF

  • GridPlateCapacitance

    5.1 pF

  • PlateCapacitanceSystem1

    0.91 pF

    Section1

  • PlateCapacitanceSystem2

    0.81 pF

    Section2

Data set 02

2026 JJ Electronic

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Uk/f

    200 V

    Published value

Characteristics

  • Ua

    150 V

    Published value

  • Ug

    -4 V

    Published value

  • Ia

    18 mA

    Published value

  • S

    9500 µS

    Published value

  • Ri

    2.3 kΩ

    Published value

  • µ

    22

    Published value

Capacitance

  • cg/k

    5.8

    Published value

  • ca

    0.91

    Published value

  • cg/a

    5.1

    Published value