Tube cross-reference
20A3 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the 20A3 specialized - thyratron. Compare core specifications and verify every restriction before using a replacement.
Replacement tubes for 20A3
The following tubes are recorded as possible replacements for 20A3. This direction does not establish that 20A3 can replace them.
Specialized - Thyratron
The database records 2D21 as a possible replacement for20A3.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Specialized - Thyratron | Specialized - Thyratron |
| Construction | Tetrode | Thyratron |
| Base | Not recorded | B7G |
| Socket | Not recorded | B7G |
| Base pins | Not recorded | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.6 A | 0.6 A |
Where 20A3 can be used as the replacement
In these recorded relationships, 20A3 is the replacement tube. The listed original tubes are not automatically suitable as replacements for 20A3.
Specialized - Thyratron
The database records 20A3 as a possible replacement for2D21.
No special restrictions are recorded for this substitution.
| Specification | 20A3 replacement | Original tube |
|---|---|---|
| Tube type | Specialized - Thyratron | Specialized - Thyratron |
| Construction | Tetrode | Thyratron |
| Base | Not recorded | B7G |
| Socket | Not recorded | B7G |
| Base pins | Not recorded | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.6 A | 0.6 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 20A3 specifications →