EZ40

Rectifier — Rimlock

Philips

Known Equivalents & Substitutes

6BT4CV3891U150

Similar Tubes (Not Drop-In Compatible)

Noval-base successor with identical electrical ratings — EZ40 is Rimlock, different pinout

Electrical Specifications

Absolute Maximum

Anode Voltage (max)Max AC Voltage per Anode (RMS)350V

Heater-to-Cathode Voltage (max)Heater-to-Cathode Voltage (max)500V

Rectifier

Peak Inverse VoltagePeak Inverse Voltage1,000V

Voltage Drop (typical)Voltage Drop (per plate at 90 mA)17V

Max C-input Filter CapacitorMax C-input Filter Capacitor50µF

DC Output Current (max)DC Output Current (max)90mA

Min Series Resistance (C-input)Min Series Resistance per Anode (at 2x350 Vrms)

Heater

Heater VoltageHeater Voltage6.3V

Heater CurrentHeater Current0.6A

Notes

A minimum series resistance per anode is mandatory to limit surge current when charging the input capacitor. Required values vary with transformer voltage: 125 ohm at 2x250 V, 175 ohm at 2x275 V, 215 ohm at 2x300 V, 300 ohm at 2x350 V.
Pins 3, 4, and 5 are internal connections — do not ground or connect externally.
The EZ80 (6V4) is the Noval-base successor with identical electrical ratings but different pinout — not pin-compatible.
The maximum permissible transformer voltage of 350 Vrms is the no-load secondary voltage. The heater can be fed from the same transformer winding as other valves due to the high heater-cathode insulation (500 V max).
Warm-up time is approximately 35 seconds, which is longer than typical output valves — this prevents HT from appearing before the other valves are ready to draw current.
DC output voltage with capacitor-input filter (CL=50 uF) at 90 mA: approximately 260 V at 2x250 Vrms, 285 V at 2x275 Vrms, 310 V at 2x300 Vrms, 360 V at 2x350 Vrms.

Pin Layout — Rimlock

1Heater

2Anode 2

3Internal Connection

4

References