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Voltage Pentode - Sharp Cutoff (single) ·Pentode

CV138

Pentode designed for radio-frequency or wide-band amplifier service in receiving or electronic equipment.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B7G
Base pins
7
Nominal heater
6.3 V / 300 mA

Description

Commercial equivalent designation explicitly printed for type 6AM6, a high-slope miniature RF and wide-band pentode.

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
7
Nominal heater voltage
6.3 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

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
1000000 Ω
Transconductance
0.0073 S
Amplification factor
70
Max plate voltage
275 V
Max screen voltage
275 V
Max plate dissipation
2.5 W
Max screen dissipation
0.8 W

Published ratings and characteristics promoted semantically from source; repeated identical physical sections compressed where applicable.

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

1958 Brimar Radio Valve No 7

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Voltage

    250 V

  • Plate Current

    10 mA

  • Screen Voltage

    250 V

  • Screen Current

    2.6 mA

Characteristic

  • Plate Resistance

    1 Mohm

  • Transconductance

    7300 µS

  • Amplification Factor

    70

  • Frequency Changer Maximum

    100 MHz