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Power - Triode ·Triode

3BI51A

Oxide-coated filament power triode documented for power service. The available manufacturer source gives triode characteristics and interelectrode capacitances but is comparatively sparse about a narrower specialized application.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
MEDIUM4BAYONET
Base pins
4
Nominal heater
4.5 V / 1.6 A

Description

Oxide-coated filament power triode.

Socket description

Medium 4-contact bayonet base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
MEDIUM4BAYONET
Base pins
4
Nominal heater voltage
4.5 V
Nominal heater current
1.6 A
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

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
3500 Ω
Amplification factor
7
Max plate voltage
400 V
Max plate dissipation
15 W
Max cathode current
50 mA

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

1947 Standard Valves

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Grid-anode capacitance

    6.2 pF

  • Grid-cathode/filament capacitance

    5 pF

  • Anode-cathode/filament capacitance

    3.2 pF

Other

  • Maximum direct grid current

    10 mA