6F5P — Triode-Pentode, Noval | TubeofileKnown Equivalents & Substitutes
ECL856GV8
Similar Tubes (Not Drop-In Compatible)
6F3P
Soviet ECL82/6BM8 equivalent — similar triode-pentode concept but different characteristicsECL86 equivalent — similar concept but different electrical characteristics ECL86
Later triode-pentode (6GW8) — higher pentode output, different pinoutElectrical Specifications
Section 1 — Triode
Absolute Maximum
Anode Voltage (max)Anode Voltage (max)300V
Anode Dissipation (max)Anode Dissipation (max)2W
Typical Operating
Anode Voltage (typical)Anode Voltage200V
Grid 1 Bias VoltageGrid Voltage-1V
Anode CurrentAnode Current10mA
Anode ResistanceAnode Resistance7,800Ω
TransconductanceTransconductance
Section 2 — Pentode
Absolute Maximum
Anode Voltage (max)Anode Voltage (max)300V
Screen Voltage (max)Screen Voltage (max)300V
Anode Dissipation (max)Anode Dissipation (max)9W
Screen Dissipation (max)Screen Dissipation (max)2W
Heater
Heater VoltageHeater Voltage6.3V
Heater CurrentHeater Current0.76A
Notes
- Cyrillic designation: 6Ф5П. Russian_equivalents.json confirms: 6F5P ≈ 6GV8, ECL85.
- Foreign_substitutes.json also confirms: ECL86 → 6F5P (noting ECL86/6GW8 as Western substitute).
- The triode section provides voltage gain, and the pentode section provides power output — a complete audio amplifier in one envelope.
- Commonly used in Soviet television audio output stages and compact radio receivers.
- The ECL85 was designed for relatively low supply voltages (~200V B+).
Pin Layout — Noval
1Pentode Anode
2Pentode Screen Grid
3Pentode Control Grid
6mA/V
Amplification Factor (μ)Amplification Factor (μ)47—
Anode Voltage (typical)Anode Voltage
200V
Screen Voltage (typical)Screen Voltage200V
Grid 1 Bias VoltageGrid 1 Bias Voltage-7.5V
Anode CurrentAnode Current40mA
Screen CurrentScreen Current6mA
TransconductanceTransconductance10mA/V
Output
Output PowerOutput Power3.4W
9Pentode Suppressor / Internal Shield