What is the 83 vacuum tube?

The 83 is a rectifier vacuum tube designed for rectifier applications. Mercury vapor blue glow. Constant 15V drop..

What is a 83 substitute or equivalent?

Direct equivalents to the 83 include VT-83. 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.

Is the 83 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 83 as Sought-after 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 83 sound like?

Mercury vapor blue glow. Constant 15V drop.. 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.

83 Rectifier Vacuum Tube

Also known as VT-83

Full-wave rectifier for vacuum tube power supply designs

RectifierHeater 5 V · 3 AUX-4RCA·Sylvania 1933

Max DC output current: 225mA
Peak inverse voltage: 1550V
Max RMS input per anode: 550V
Peak anode current: 1A

Characteristics

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

HeaterDirectly heated

Specifications of 83 — Heater
Heater voltageVh	5 V
Heater currentIh	3 A

Rectifier limitsDatasheet maximum ratings — not to be exceeded

Specifications of 83 — Rectifier limits
Max RMS input voltage per anode	550 V
Io max (DC output current)	225 mA
Peak inverse voltage (PIV)	1550 V
Peak anode current	1 A
Tube voltage drop at Io	15 V
Min series resistance per anode	50 Ω

Mechanical

Specifications of 83 — Mechanical
Base	UX-4
Rarity	Sought-after
Pinout

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

Using this tube

Interactive loadline calculator not available for this tube yet — it needs calibrated Koren or Ayumi parameters.

Applications

Power supply rectification

Generic rectifier rectifier stage

Headphone amp

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : cap audit 2026-05-09

Manufacturer datasheets

4 manufacturer datasheets cross-checked for 834 verified

83 DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: cap audit 2026-05-09
Reviewed: 2026-05-29
Status: DataModelCalc
Model: under review

Context

The 83 is a directly-heated rectifier from RCA·Sylvania, introduced around 1933. Commonly used in rectifier applications. Mercury vapor blue glow. Constant 15V drop.

History

Introduced: 1933
Manufacturer: RCA·Sylvania
Era: Pre-War

METRIX TESTER