Semi-remote cutoff twin triode on same 9AJ base — may not work in all circuits per Sams substitution guide
6BK7A
Semi-remote cutoff twin triode on same 9AJ base — may not work in all circuits per Sams substitution guide
6BK7B
Semi-remote cutoff twin triode on same 9AJ base — may not work in all circuits per Sams substitution guide
Electrical Specifications
Absolute Maximum
Anode Voltage (max)Plate Voltage (max)250V
Anode Dissipation (max)Plate Dissipation (max)2W
Cathode Current (max)Cathode Current (max)20mA
Heater-to-Cathode Voltage (max)Heater-Cathode Voltage (max)200V
Max Grid Resistor
Notes
Pin 9 (internal shield) should be grounded; with external shield (RETMA 315) connected to pin 9.
In cascode amplifier service with both sections in series, Va_max may be as high as 300 V under cutoff conditions.
4BQ7A (Vh=4.2V, Ih=0.6A) and 5BQ7A (Vh=5.6V, Ih=0.45A) are heater-voltage variants with controlled warm-up characteristics for series-string television receivers.
Replaced the 6BQ7 within two years of its introduction, offering approximately 12% higher gain with otherwise identical characteristics.
Pin Layout — Noval
1Plate (Section 2)
2Grid (Section 2)
3Cathode (Section 2)
Socket-Compatible Tubes ⚠ Not electrically compatible