Tube cross-reference
1F4 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the 1F4 power - pentode single (not beam) (under 10w). Compare core specifications and verify every restriction before using a replacement.
Replacement tubes for 1F4
The following tubes are recorded as possible replacements for 1F4. This direction does not establish that 1F4 can replace them.
Power - Pentode (NOT beam)
The database records 2101 as a possible replacement for1F4.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Power - Pentode Single (NOT beam) (under 10W) | Power - Pentode (NOT beam) |
| Construction | Pentode | Pentode |
| Base | 5K | Not recorded |
| Socket | UX5 | Not recorded |
| Base pins | 5 | Not recorded |
| Sections | 1 | 1 |
| Heater voltage | 2 V | 2 V |
| Heater current | 0.12 A | 0.12 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 1F4 specifications →