7AD7 — Power Pentode, Loctal | TubeofileKnown Equivalents & Substitutes
No known equivalents. If you know of any, use the ⚑ Report Issue button above.
Similar Tubes (Not Drop-In Compatible)
6CH6
Brans lists in same group — similar sharp-cutoff pentode but different base (Noval vs Loctal)6CL6
Brans lists in same group — similar characteristics but Noval baseBrans lists in same group — similar power pentode but Noval base, different era Brans lists in same group — European equivalent type but different base Electrical Specifications
Absolute Maximum
Anode Voltage (max)Max Plate Voltage300V
Anode Dissipation (max)Max Plate Dissipation10W
Screen Voltage (max)Max Screen Voltage300V
Screen Dissipation (max)Max Screen Dissipation1.2W
Heater-to-Cathode Voltage (max)
Notes
- Tung-Sol datasheet marked as 'Tentative Data' (1948).
- Two typical operating conditions given: Class A1 amplifier (Va=300V, Vg2=150V) and Class A1 television amplifier (Va=300V, Vg2=125V).
- Maximum grid #4 circuit resistance: 0.25 Mohm (fixed bias), 1 Mohm (self-bias).
- GE Essential Characteristics lists max plate dissipation as 10W, screen voltage max 150V.
- Grid #3 voltage connected to pin #7 at socket (cathode connection).
Pin Layout — Loctal
1Heater
2Plate
3Screen Grid (g2)
4
Socket-Compatible Tubes ⚠ Not electrically compatible
Max Heater-Cathode Voltage
90V
Typical Operating
Anode Voltage (typical)Plate Voltage300V
Grid 1 Bias VoltageGrid Voltage-3V
Anode CurrentPlate Current28mA
Screen VoltageScreen Voltage150V
Screen CurrentScreen Current7mA
Anode ResistancePlate Resistance300,000Ω
TransconductanceTransconductance9.5mA/V
Capacitances
Grid-to-Plate CapacitanceGrid-Plate Capacitance0.03pF
Input CapacitanceInput Capacitance11.5pF
Output CapacitanceOutput Capacitance7.5pF
Heater
Heater VoltageHeater Voltage6.3V
Heater CurrentHeater Current0.6A
Grid #3 (connected to pin #7 at socket)
5Grid #5 (connected to pin #7 at socket)