Tube cross-reference
X18 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the X18 voltage pentode or tetrode (under 100v). Compare core specifications and verify every restriction before using a replacement.
Replacement tubes for X18
The following tubes are recorded as possible replacements for X18. This direction does not establish that X18 can replace them.
Voltage Pentode or Tetrode (under 100V)
The database records 1AC6 as a possible replacement forX18.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode or Tetrode (under 100V) |
| Construction | Heptode | Heptode |
| Base | Not recorded | 7DH |
| Socket | B7G | B7G |
| Base pins | Not recorded | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.4 V |
| Heater current | Not recorded | 0.05 A |
Where X18 can be used as the replacement
In these recorded relationships, X18 is the replacement tube. The listed original tubes are not automatically suitable as replacements for X18.
Voltage Pentode or Tetrode (under 100V)
The database records X18 as a possible replacement for1AC6.
No special restrictions are recorded for this substitution.
| Specification | X18 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode or Tetrode (under 100V) |
| Construction | Heptode | Heptode |
| Base | Not recorded | 7DH |
| Socket | B7G | B7G |
| Base pins | Not recorded | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.4 V |
| Heater current | Not recorded | 0.05 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 X18 specifications →