Tube cross-reference
6661 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the 6661 voltage pentode - sharp cutoff (single). Compare core specifications and verify every restriction before using a replacement.
Exact variations of 6661
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.
6BH6 Voltage Pentode - Sharp Cutoff (single)
- Base
- 7CM
- Socket
- B7G
- Base pins
- 7
- Sections
- 1
- Heater voltage
- 6.3 V
- Heater current
- 0.15 A
Replacement tubes for 6661
The following tubes are recorded as possible replacements for 6661. This direction does not establish that 6661 can replace them.
Voltage Pentode - Sharp Cutoff (single)
The database records 6BH6 as a possible replacement for6661.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode - Sharp Cutoff (single) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | Not recorded | 7CM |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.15 A | 0.15 A |
Where 6661 can be used as the replacement
In these recorded relationships, 6661 is the replacement tube. The listed original tubes are not automatically suitable as replacements for 6661.
Voltage Pentode - Sharp Cutoff (single)
The database records 6661 as a possible replacement for6BH6.
No special restrictions are recorded for this substitution.
| Specification | 6661 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode - Sharp Cutoff (single) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | Not recorded | 7CM |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.15 A | 0.15 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 6661 specifications →