Tube cross-reference
KT77 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the KT77 power - beam (not sweep). Compare core specifications and verify every restriction before using a replacement.
Replacement tubes for KT77
The following tubes are recorded as possible replacements for KT77. This direction does not establish that KT77 can replace them.
Power - Beam (NOT sweep)
The database records 6CA7 as a possible replacement forKT77.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Power - Beam (NOT sweep) | Power - Beam (NOT sweep) |
| Construction | BeamPower | BeamPower |
| Base | Not recorded | 8ET |
| Socket | IO | IO |
| Base pins | 8 | 8 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 1.4 A | 1.5 A |
Where KT77 can be used as the replacement
In these recorded relationships, KT77 is the replacement tube. The listed original tubes are not automatically suitable as replacements for KT77.
Power - Beam (NOT sweep)
The database records KT77 as a possible replacement for6CA7.
No special restrictions are recorded for this substitution.
| Specification | KT77 replacement | Original tube |
|---|---|---|
| Tube type | Power - Beam (NOT sweep) | Power - Beam (NOT sweep) |
| Construction | BeamPower | BeamPower |
| Base | Not recorded | 8ET |
| Socket | IO | IO |
| Base pins | 8 | 8 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 1.4 A | 1.5 A |
Power - Beam (NOT sweep)
The database records KT77 as a possible replacement for7581.
No special restrictions are recorded for this substitution.
| Specification | KT77 replacement | Original tube |
|---|---|---|
| Tube type | Power - Beam (NOT sweep) | Power - Beam (NOT sweep) |
| Construction | BeamPower | BeamPower |
| Base | Not recorded | Not recorded |
| Socket | IO | IO |
| Base pins | 8 | 8 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 1.4 A | 0.9 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 KT77 specifications →