Tube cross-reference
5556 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the 5556 power - triode. Compare core specifications and verify every restriction before using a replacement.
Exact variations of 5556
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.
PJ8 Power - Triode Single (under 10W)
- Base
- Not recorded
- Socket
- B4B
- Base pins
- Not recorded
- Sections
- 1
- Heater voltage
- 4.5 V
- Heater current
- 1.1 A
Replacement tubes for 5556
The following tubes are recorded as possible replacements for 5556. This direction does not establish that 5556 can replace them.
Power - Triode Single (under 10W)
The database records PJ8 as a possible replacement for5556.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Power - Triode | Power - Triode Single (under 10W) |
| Construction | Triode | Triode |
| Base | Not recorded | Not recorded |
| Socket | J4 | B4B |
| Base pins | 4 | Not recorded |
| Sections | 1 | 1 |
| Heater voltage | 4.5 V | 4.5 V |
| Heater current | 1.1 A | 1.1 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 5556 specifications →