12AX7
| 12AX7 | |
|---|---|
12AX7 | |
| Classification | Dual triode |
| Service | Class-A amplifier |
| Height | 2.2 in (56 mm) |
| Diameter | 0.8 in (20 mm) |
| Cathode | |
| Cathode type | Indirectly heated |
| Heater voltage | 12.6 V (series) 6.3 V (parallel) |
| Heater current | 150 mA (series) 300 mA (parallel) |
| Anode | |
| Max dissipation Watts | 1 per section |
| Max voltage | 300 V |
| Socket connections | |
| Typical class-A amplifier operation | |
| Amplification factor | 100 |
| Anode voltage | 250 V |
| Anode current | 1.2 mA |
| Bias voltage | −2 V |
| Anode resistance | 62.5 kΩ |
| References | |
| Sylvania 12AX7 datasheet | |
12AX7 (also known as ECC83) is a miniature dual-triode vacuum tube with high voltage gain. Developed around 1946 by RCA engineers in Camden, New Jersey, under developmental number A-4522, it was released for public sale under the 12AX7 identifier on September 15, 1947.
The 12AX7 was originally intended as replacement for the 6SL7 family of dual-triode amplifier tubes for audio applications. As a popular choice for guitar tube amplifiers, its ongoing use in such equipment makes it one of the few small-signal vacuum tubes in continuous production since it was introduced.