Tube cross-reference
U309 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the U309 rectifier - damper diode. Compare core specifications and verify every restriction before using a replacement.
Replacement tubes for U309
The following tubes are recorded as possible replacements for U309. This direction does not establish that U309 can replace them.
Rectifier - Damper Diode
The database records 19X3 as a possible replacement forU309.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Rectifier - Damper Diode | Rectifier - Damper Diode |
| Construction | Rectifier | Rectifier |
| Base | Not recorded | 9BM |
| Socket | B9A | Not recorded |
| Base pins | Not recorded | 9 |
| Sections | 1 | 1 |
| Heater voltage | 20 V | 19 V |
| Heater current | 0.3 A | 0.3 A |
Where U309 can be used as the replacement
In these recorded relationships, U309 is the replacement tube. The listed original tubes are not automatically suitable as replacements for U309.
Rectifier - Damper Diode
The database records U309 as a possible replacement for19X3.
No special restrictions are recorded for this substitution.
| Specification | U309 replacement | Original tube |
|---|---|---|
| Tube type | Rectifier - Damper Diode | Rectifier - Damper Diode |
| Construction | Rectifier | Rectifier |
| Base | Not recorded | 9BM |
| Socket | B9A | Not recorded |
| Base pins | Not recorded | 9 |
| Sections | 1 | 1 |
| Heater voltage | 20 V | 19 V |
| Heater current | 0.3 A | 0.3 A |
Verify before substituting
Matching a base or heater voltage is not enough to prove that two tubes are interchangeable. Check pin connections, heater current, maximum ratings, bias requirements, warm-up behavior, and the equipment manufacturer’s service documentation before making a substitution.
View the complete U309 specifications →