Tube cross-reference
2C51 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the 2C51 voltage - dual triode (similar high frequency). Compare core specifications and verify every restriction before using a replacement.
Exact variations of 2C51
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.
396A Voltage - Dual Triode (similar high frequency)
- Base
- E9-1
- Socket
- B9A
- Base pins
- 9
- Sections
- 2
- Heater voltage
- 6.3 V
- Heater current
- 0.3 A
Replacement tubes for 2C51
The following tubes are recorded as possible replacements for 2C51. This direction does not establish that 2C51 can replace them.
Voltage - Dual Triode (similar high frequency)
The database records 396A as a possible replacement for2C51.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage - Dual Triode (similar high frequency) | Voltage - Dual Triode (similar high frequency) |
| Construction | Triode-Triode | Triode-Triode |
| Base | 8CY | E9-1 |
| 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 |
Voltage - Dual Triode (similar high frequency)
The database records 5670 as a possible replacement for2C51.
- Parallel heater circuits only
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage - Dual Triode (similar high frequency) | Voltage - Dual Triode (similar high frequency) |
| Construction | Triode-Triode | Triode-Triode |
| Base | 8CY | E9-1 |
| Socket | B9A | B9A |
| Base pins | 9 | 9 |
| Sections | 2 | 2 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.3 A | 0.35 A |
Voltage - Dual Triode (similar high frequency)
The database records 5670WA as a possible replacement for2C51.
- Parallel heater circuits only
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage - Dual Triode (similar high frequency) | Voltage - Dual Triode (similar high frequency) |
| Construction | Triode-Triode | Triode-Triode |
| Base | 8CY | 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 | 0.35 A |
Power - Beam (NOT sweep)
The database records 6185 as a possible replacement for2C51.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage - Dual Triode (similar high frequency) | Power - Beam (NOT sweep) |
| Construction | Triode-Triode | BeamPower |
| Base | 8CY | Not recorded |
| Socket | B9A | B12C |
| Base pins | 9 | 12 |
| Sections | 2 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.3 A | 0.8 A |
Voltage - Dual Triode (similar)
The database records 6385 as a possible replacement for2C51.
- Parallel heater circuits only
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage - Dual Triode (similar high frequency) | Voltage - Dual Triode (similar) |
| Construction | Triode-Triode | Triode-Triode |
| Base | 8CY | 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 | 0.5 A |
Where 2C51 can be used as the replacement
In these recorded relationships, 2C51 is the replacement tube. The listed original tubes are not automatically suitable as replacements for 2C51.
Voltage - Dual Triode (similar high frequency)
The database records 2C51 as a possible replacement for396A.
No special restrictions are recorded for this substitution.
| Specification | 2C51 replacement | Original tube |
|---|---|---|
| Tube type | Voltage - Dual Triode (similar high frequency) | Voltage - Dual Triode (similar high frequency) |
| Construction | Triode-Triode | Triode-Triode |
| Base | 8CY | E9-1 |
| 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 2C51 specifications →