Tube cross-reference
1AJ4 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the 1AJ4 voltage pentode or tetrode (under 100v). Compare core specifications and verify every restriction before using a replacement.
Exact variations of 1AJ4
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.
Replacement tubes for 1AJ4
The following tubes are recorded as possible replacements for 1AJ4. This direction does not establish that 1AJ4 can replace them.
Specialized - Ballast
The database records 1F1 as a possible replacement for1AJ4.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Specialized - Ballast |
| Construction | Pentode | Ballast |
| Base | 6AR | Not recorded |
| Socket | B7G | UX4 |
| Base pins | 7 | Not recorded |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | Not recorded |
| Heater current | 0.025 A | 0.72 A |
Voltage Pentode - Remote Cutoff (single)
The database records DF96 as a possible replacement for1AJ4.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode - Remote Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | 6AR | B7G |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.4 V |
| Heater current | 0.025 A | 0.025 A |
Voltage Pentode - Sharp Cutoff (single)
The database records 1AE4 as a possible replacement for1AJ4.
- Parallel heater circuits only
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | 6AR | 6AR |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.25 V |
| Heater current | 0.025 A | 0.1 A |
Voltage Pentode - Sharp Cutoff (single)
The database records 1AF4 as a possible replacement for1AJ4.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | 6AR | 6AR |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.4 V |
| Heater current | 0.025 A | 0.025 A |
Voltage Pentode or Tetrode (under 100V)
The database records 1T4 as a possible replacement for1AJ4.
- Parallel heater circuits only
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode or Tetrode (under 100V) |
| Construction | Pentode | Pentode |
| Base | 6AR | 8AR |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.4 V |
| Heater current | 0.025 A | 0.05 A |
Where 1AJ4 can be used as the replacement
In these recorded relationships, 1AJ4 is the replacement tube. The listed original tubes are not automatically suitable as replacements for 1AJ4.
Specialized - Ballast
The database records 1AJ4 as a possible replacement for1F1.
No special restrictions are recorded for this substitution.
| Specification | 1AJ4 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Specialized - Ballast |
| Construction | Pentode | Ballast |
| Base | 6AR | Not recorded |
| Socket | B7G | UX4 |
| Base pins | 7 | Not recorded |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | Not recorded |
| Heater current | 0.025 A | 0.72 A |
Voltage Pentode - Remote Cutoff (single)
The database records 1AJ4 as a possible replacement forDF96.
No special restrictions are recorded for this substitution.
| Specification | 1AJ4 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode - Remote Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | 6AR | B7G |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.4 V |
| Heater current | 0.025 A | 0.025 A |
Voltage Pentode - Sharp Cutoff (single)
The database records 1AJ4 as a possible replacement for1AF4.
No special restrictions are recorded for this substitution.
| Specification | 1AJ4 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | 6AR | 6AR |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.4 V |
| Heater current | 0.025 A | 0.025 A |
Voltage Pentode or Tetrode (under 100V)
The database records 1AJ4 as a possible replacement for1T4.
- Parallel heater circuits only
| Specification | 1AJ4 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (under 100V) | Voltage Pentode or Tetrode (under 100V) |
| Construction | Pentode | Pentode |
| Base | 6AR | 8AR |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 1.4 V | 1.4 V |
| Heater current | 0.025 A | 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 1AJ4 specifications →