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Rectifier - Full Wave ·Pentode-Rectifier

25A7GT

GT-envelope combination rectifier and power pentode, interchangeable with 25A7G and intended for receiver power-supply and audio-output service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
IO
Base pins
8
Nominal heater
25 V / 300 mA

Description

The Hytron 2BA7GT is a glasu tube equipped with a small octal base and may be ussd Inter- changeadbly with the 25A7G glasa tube.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
IO
Base pins
8
Nominal heater voltage
25 V
Nominal heater current
300 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

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
50000 Ω
Transconductance
0.0018 S
Max plate voltage
117 V
Max screen voltage
117 V
Max plate dissipation
2.25 W
Max screen dissipation
0.8 W

Section 2

Rectifier

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
350 V
Rectifier nominal output current
75 mA
Rectifier peak forward current
450 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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Voltage

    100 V

    ClassA

  • Screen Voltage

    100 V

    ClassA

  • Power Output

    0.77 W

    ClassA

SECTION 2

Rectifier

Other

  • Maximum AC Plate Voltage RMS

    117 V

  • Minimum Effective Plate Supply Impedance

    15 ohm

Characteristic

  • Tube Voltage Drop

    23 V

    PlateCurrent=150mA