Contains a triode section with similar high-mu characteristics, but also includes two diode sections (duplex-diode triode)
Electrical Specifications
Absolute Maximum
Anode Voltage (max)Max. Plate Voltage300V
Max Grid ResistorMax. Grid Resistor10MΩ
Typical Operating
Anode Voltage (typical)Plate Voltage (typical)250V
Grid 1 Bias VoltageGrid Voltage-2V
Notes
Electrically identical to the 6SF5 except for 12.6V/0.15A heater (vs 6.3V/0.3A).
Shell is internally connected to cathode (pin 2). In circuits where the cathode is not directly connected to the heater, the heater-to-cathode voltage should be kept as low as possible.
Base designation 6AB (6-pin Octal, metal shell). GT variant uses G-6AB (intermediate shell, 6-pin Octal).
Tung-Sol datasheet gives two operating points: Va=100V/Vg=-1V (ra=85000, gm=1150 umhos) and Va=250V/Vg=-2V (ra=66000, gm=1500 umhos). Both at zero-bias resistance-coupled Class A1.
At Va=250V, typical voltage gain is 66-71 depending on load resistor (0.25-1.0 Mohm).
Pin Layout — Octal
1No Connection
2Cathode (shell)
3Grid
4
Socket-Compatible Tubes ⚠ Not electrically compatible