- Base
- Refer to variations
- Socket code
- B9A
- Sections
- 2
- Heater
- 12 V / 100 mA
- Plate
- S1: 250 V / 0.5 W · S2: 250 V
B9A - Small-button Noval 9-contact
Series-heater tuning indicator with amplifying triode, designed for receiver tuning or modulation-control service with a sensitive fluorescent visual display.