4028A

High-mu ceramic-metal pencil triode for pulsed RF amplification, oscillation, and frequency multiplication into the multi-gigahertz region. High transconductance and compact low-inductance construction provide strong gain in microwave-frequency pulse circuits.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: -
Base pins: -
Nominal heater: 6.3 V / 300 mA

Description

High-mu ceramic-metal pencil triode for pulse, oscillator, amplifier, and frequency-multiplier service to several GHz.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: -
Base pins: -
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

Triode

X-ray radiationInterelectrode capacitances

Transconductance: 0.0225 S
Amplification factor: 70
Max plate voltage: 300 V
Max plate dissipation: 8 W
Max grid dissipation: 3 W
Max cathode current: 35 mA

High-mu ceramic-metal pencil triode. Plate resistance derived from published μ/gm at the published characteristic point.

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

1971 RCA HB3 Binder 6 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

Heater/filament voltage
6.3 V
Heater/filament current
300 mA
Maximum plate voltage
300 V
Maximum plate dissipation
8 W
Typical pulsed plate voltage
2000 V
PulseRF
Useful power output
1000 W
PulseRF
Peak heater-cathode voltage
60 V
BothPolarities
RF amplifier useful power output
6 W
CW

Characteristic

Amplification factor
70
Transconductance
22500 uS
Plate resistance
3111.111 ohm
DerivedFromPublishedMuAndGm