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Voltage - Triple Triode ·Triode-Triode-Triode

7689

High-reliability high-mu triple triode for instrumentation; each section is electrically equivalent to one section of a 12AX7.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
E12-66 / 12BA
Socket code
B12C
Base pins
12
Nominal heater
6.3 V / 450 mA

Description

High-mu triple triode; each section electrically equivalent to one section of 12AX7; high-reliability instrumentation service.

Socket description

Duodecar 12-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
E12-66 / 12BA
Socket code
B12C
Base pins
12
Nominal heater voltage
6.3 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

E12-66 / 12BA - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

3 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
80000 Ω
Transconductance
0.00125 S
Amplification factor
100
Max plate voltage
330 V
Max plate dissipation
1.1 W
Max cathode current
20 mA

Promoted from 250 V characteristic point; design-maximum values apply to each identical section.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
80000 Ω
Transconductance
0.00125 S
Amplification factor
100
Max plate voltage
330 V
Max plate dissipation
1.1 W
Max cathode current
20 mA

Physical triode section added to align rows with SectionCount.

Section 3

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
80000 Ω
Transconductance
0.00125 S
Amplification factor
100
Max plate voltage
330 V
Max plate dissipation
1.1 W
Max cathode current
20 mA

Physical triode section added to align rows with SectionCount.

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 CBS Hytron

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Plate voltage

    100 V

    ClassA

  • Plate resistance

    80000 Ohm

    ClassA;Va=100V

  • Transconductance

    1250 uS

    ClassA;Va=100V

  • Amplification factor

    100 ratio

    ClassA

  • Plate current

    0.5 mA

    ClassA;Va=100V

  • Plate voltage

    250 V

    ClassA

  • Plate current

    1.2 mA

    ClassA;Va=250V