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Power - Triode Single (under 10W) ·Triode

7738

High-mu miniature power triode designed for continuous Class C RF amplifier service. Its 5 W plate dissipation and useful operation to about 200 MHz make it a compact VHF transmitting or driver tube.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B7G
Base pins
-
Nominal heater
6.3 V / 225 mA

Description

High-mu miniature triode for continuous Class-C RF amplifier service around 200 MHz.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B7G
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
225 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

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0095 S
Amplification factor
33
Max plate voltage
330 V
Max plate dissipation
5 W
Max cathode current
40 mA

Published source values promoted where applicable; additional source values retained as parameters.

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

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater voltage

    6.3 V

  • Heater current

    225 mA

  • Maximum useful frequency

    200 MHz

Other

  • Heater voltage tolerance

    +/-0.6 V

  • Plate voltage maximum

    330 V

    ClassC

  • Plate dissipation maximum

    5 W

    ClassC

  • Plate input maximum

    7.5 W

    ClassC

  • Cathode current maximum

    40 mA

    ClassC

  • Grid current maximum

    10 mA

    ClassC

  • Negative grid voltage maximum

    -50 V

Application

  • Application

    Continuous Class-C RF amplifier