Tube cross-reference
6F33 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the 6F33 voltage pentode or tetrode (with diode). Compare core specifications and verify every restriction before using a replacement.
Replacement tubes for 6F33
The following tubes are recorded as possible replacements for 6F33. This direction does not establish that 6F33 can replace them.
Voltage Pentode - Sharp Cutoff (single)
The database records 6AS6 as a possible replacement for6F33.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (with diode) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Diode-Pentode | Pentode |
| Base | B7G | E7-1 |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 2 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.35 A | 0.175 A |
Where 6F33 can be used as the replacement
In these recorded relationships, 6F33 is the replacement tube. The listed original tubes are not automatically suitable as replacements for 6F33.
Voltage Pentode - Sharp Cutoff (single)
The database records 6F33 as a possible replacement for6AS6.
No special restrictions are recorded for this substitution.
| Specification | 6F33 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode or Tetrode (with diode) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Diode-Pentode | Pentode |
| Base | B7G | E7-1 |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 2 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.35 A | 0.175 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 6F33 specifications →