Tube cross-reference
EM81 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the EM81 tuning indicator. Compare core specifications and verify every restriction before using a replacement.
Exact variations of EM81
These designations belong to the same electrical variation group. Their names may differ because of international standards, manufacturing tolerances, or materials, but they are recorded as electrically equivalent—not merely substitutes.
6DA5 Tuning Indicator
- Base
- Not recorded
- Socket
- B9A
- Base pins
- 9
- Sections
- 2
- Heater voltage
- 6.3 V
- Heater current
- 0.3 A
Replacement tubes for EM81
The following tubes are recorded as possible replacements for EM81. This direction does not establish that EM81 can replace them.
Tuning Indicator
The database records 6DA5 as a possible replacement forEM81.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Tuning Indicator | Tuning Indicator |
| Construction | Triode-TuningIndicator | Triode-TuningIndicator |
| Base | Not recorded | Not recorded |
| Socket | B9A | B9A |
| Base pins | 9 | 9 |
| Sections | 2 | 2 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.3 A | 0.3 A |
Where EM81 can be used as the replacement
In these recorded relationships, EM81 is the replacement tube. The listed original tubes are not automatically suitable as replacements for EM81.
Tuning Indicator
The database records EM81 as a possible replacement for6BR5.
No special restrictions are recorded for this substitution.
| Specification | EM81 replacement | Original tube |
|---|---|---|
| Tube type | Tuning Indicator | Tuning Indicator |
| Construction | Triode-TuningIndicator | Triode-TuningIndicator |
| Base | Not recorded | Not recorded |
| Socket | B9A | B9A |
| Base pins | 9 | 9 |
| Sections | 2 | 2 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.3 A | 0.3 A |
Tuning Indicator
The database records EM81 as a possible replacement for6DA5.
No special restrictions are recorded for this substitution.
| Specification | EM81 replacement | Original tube |
|---|---|---|
| Tube type | Tuning Indicator | Tuning Indicator |
| Construction | Triode-TuningIndicator | Triode-TuningIndicator |
| Base | Not recorded | Not recorded |
| Socket | B9A | B9A |
| Base pins | 9 | 9 |
| Sections | 2 | 2 |
| Heater voltage | 6.3 V | 6.3 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 EM81 specifications →