384A

Miniature Western Electric pentode with published Class-A characteristics, intended for low-level amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: UX4
Base pins: 4
Nominal heater: 6.3 V / 150 mA

Description

Miniature pentode with published Class A characteristics.

Socket description

Medium-shell UX 4-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: UX4
Base pins: 4
Nominal heater voltage: 6.3 V
Nominal heater current: 150 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: 500000 Ω
Transconductance: 0.0025 S
Max plate voltage: 250 V
Max screen voltage: 120 V
Max plate dissipation: 1.85 W
Max screen dissipation: 0.55 W
Max cathode current: 12 mA

Limiting conditions specify plate 250 V, screen grid 120 V and total cathode current 12 mA. Characteristics such as plate resistance and transconductance are supplied primarily as curves rather than a single fixed tabulated value.

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

1956 Western Electric Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

HeaterOrFilamentVoltage
6.3 V
HeaterOrFilamentCurrent
150 mA

Other

Power Output
23 dBm
ClassA

Data set 02

2026 Western Electric 300s

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

ControlGridPlateCapacitance
0.02 pF
Input Capacitance
3.1 pF
Output Capacitance
2.1 pF
MaximumSuppressorGridVoltage
120 V
MaximumScreenGridCurrent
5 mA
Maximum Heater Cathode Voltage
30 V