What is the RCA-6146b vacuum tube?

The RCA-6146b (RCA 6146B) is a tetrode vacuum tube designed for transmitting applications. HF transmitting beam..

What is a RCA-6146b substitute or equivalent?

Direct equivalents to the RCA-6146b include 8298A. These share the same pinout and operating envelope, so they can usually be swapped without circuit changes — though batch-to-batch variations between manufacturers (NOS vs current production) may shift the sonic character noticeably.

What are the key specifications of the RCA-6146b?

Amplification factor μ ≈ 4, transconductance gm ≈ 7 mA/V, max plate voltage 750 V, max plate dissipation 35 W, heater 6.3 V / 1.125 A.

Is the RCA-6146b still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the RCA-6146b as Common availability. NOS (new-old-stock) examples from RCA, Mullard, Tung-Sol, GE, Sylvania and Telefunken trade among collectors; modern production where it exists comes mostly from JJ Electronic, Electro-Harmonix, Tung-Sol (New Sensor), Genalex, and a handful of small-batch makers.

What does the RCA-6146b sound like?

HF transmitting beam.. Sonic character also depends heavily on the circuit operating point, the surrounding tubes in the stage, and the output transformer when present — use the interactive loadline calculator on this page to explore the trade-offs.

RCA-6146b RCA 6146B Tetrode Vacuum Tube

Also known as 8298A

Beam power tetrode rated at 35W for high-power output stages

TetrodeHeater 6.3 V · 1.125 AOctalRCA 1952

Plate dissipation: 35W
Max plate voltage: 750V
Transconductance: 7mA/V

RCA-6146b

Characteristics

Datasheet values, once each. Every value cites its sheet.

HeaterIndirectly heated

Specifications of RCA-6146b — Heater
Heater voltageVh	6.3 V
Heater currentIh	1.125 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of RCA-6146b — Limiting values
Plate voltageVa max	750 V
Plate dissipationPa max	35 W

Mechanical

Specifications of RCA-6146b — Mechanical
Base	Octal
Rarity	Common
Pinout

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of RCA-6146b — Small signal
Transconductance	7 mA/V
Amplification factor	4

Capacitances

Specifications of RCA-6146b — Capacitances
Input	13 pF
Grid–plate	0.22 pF
Output	8.5 pF

Charactereditorial reading, not a measurement

Specifications of RCA-6146b — Character
Gain	4%
Power	88%
Drive	50%
Linearity	95%

datasheet cited · model or editorial reading · catalogue value, no citation attached yet · nothing invented

Using this tube

Applications

High-power output

Generic tetrode transmitting stage

PA/public address

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : frostburg/worldtube 6146B (beam tetrode)Active model : Koren pentode

Manufacturer datasheets

3 manufacturer datasheets cross-checked for RCA 6146B3 verified

RCA-6146b DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: frostburg/worldtube 6146B (beam tetrode)
Reviewed: 2026-05-29
Status: DataModelCalc
Model: Koren pentode

Context

The RCA-6146b is a indirectly-heated beam tetrode from RCA, introduced around 1952. Commonly used in transmitting applications. HF transmitting beam.

History

Introduced: 1952
Manufacturer: RCA
Era: Golden Age

METRIX TESTER