Tube cross-reference
OA3A alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the OA3A voltage regulator. Compare core specifications and verify every restriction before using a replacement.
Where OA3A can be used as the replacement
In these recorded relationships, OA3A is the replacement tube. The listed original tubes are not automatically suitable as replacements for OA3A.
Voltage Regulator
The database records OA3A as a possible replacement forVR75.
No special restrictions are recorded for this substitution.
| Specification | OA3A replacement | Original tube |
|---|---|---|
| Tube type | Voltage Regulator | Voltage Regulator |
| Construction | VoltageRegulator | VoltageRegulator |
| Base | 4AJ | 4AJ |
| Socket | IO | Not recorded |
| Base pins | 8 | 4 |
| Sections | 1 | 1 |
| Heater voltage | Not recorded | Not recorded |
| Heater current | Not recorded | Not recorded |
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 OA3A specifications →