6P33P

Power Pentode — Noval

Known Equivalents & Substitutes

EL866CW5

Similar Tubes (Not Drop-In Compatible)

Soviet EL84 equivalent — similar Noval output pentode but different power rating and characteristics

Series-heater version of EL84 — different heater voltage, not compatible

Electrical Specifications

Absolute Maximum

Anode Voltage (max)Anode Voltage (max)250V

Screen Voltage (max)Screen Voltage (max)200V

Anode Dissipation (max)Anode Dissipation (max)12W

Screen Dissipation (max)Screen Dissipation (max)1.75W

Cathode Current (max)Cathode Current (max)100mA

Heater-to-Cathode Voltage (max)Heater-to-Cathode Voltage (max)100V

Typical Operating

Anode Voltage (typical)Anode Voltage170V

Screen Voltage (typical)Screen Voltage170V

Grid 1 Bias VoltageGrid 1 Bias Voltage-12.5V

Anode CurrentAnode Current70mA

Screen CurrentScreen Current

Output

Output PowerOutput Power (Class A)5.6W

Load ImpedanceLoad Impedance2,400Ω

Capacitances

Grid-to-Plate CapacitanceGrid-to-Plate Capacitance0.6pF

Input CapacitanceInput Capacitance12pF

Output CapacitanceOutput Capacitance6pF

Heater

Heater VoltageHeater Voltage6.3V

Heater CurrentHeater Current0.76A

Notes

Cyrillic designation: 6П33П. Russian_equivalents.json confirms: 6P33P ≈ 6CW5/EL86.
From 6CW5 Tung-Sol datasheet: Va=170V, Vs=170V, Vg=-12.5V, Ia=70mA, Is=5mA, gm=10000 µmhos, ra=23kΩ.
Maximum ratings: Va_max=250V, Vs_max=200V, Pa_max=12W, Ps_max=1.75W, Ik_max=100mA.
Amplification factor (g2 to g1): 8. The EL86/6CW5 is designed for relatively low supply voltages compared to EL84.
Output power: 5.6W single-ended Class A, 5.9W push-pull per pair.

Pin Layout — Noval

1Internal Connection

2Grid 1

3Cathode / Grid 3

References