0A3 / VR75 Voltage Regulator Tube – Cold-Cathode Gas Regulator (75V)

The 0A3 (VR75) is a cold-cathode, gas-filled voltage regulator tube that holds a steady 75V reference without a heated filament.

• Tube type: Cold-cathode gas voltage regulator
• Base: Octal 8-pin
• Heater: None (cold-cathode, gas-ionization type)
• Typical use: Voltage reference/regulation in vintage radio, instrument, and amplifier power supplies

Also cataloged as VR75 — the lowest-voltage member of the octal-base 0A3/0C3/0D3 regulator family.