← BrowseData: HighHigh quality — base, heater, all universal parameters present, and ≥50% of desirable parameters filled in. Safe to use for design decisions.
Known Equivalents & Substitutes
VR56CV1056BVA24710E/11402VT201
Similar Tubes (Not Drop-In Compatible)
American equivalent with similar characteristics but verify pin compatibility Low-microphonic version of EF36 with tighter manufacturing tolerances Improved low-microphonic variant of EF36/EF37 lineage Electrical Specifications
Absolute Maximum
Anode Voltage (max)Anode Voltage (max)300V
Screen Voltage (max)Screen Voltage (max)300V
Anode Dissipation (max)Anode Dissipation (max)2.5W
Typical Operating
Anode Voltage (typical)Anode Voltage (typical)250V
Notes
- Military designation VR56 (UK). Extensively used in wartime radar and communications equipment.
- The EF37 and EF37A are improved low-microphonic versions of this type.
- Octal base with top grid cap connection (pin arrangement IO/K8A).
Pin Layout — Octal
1No Connection
2Heater
3Anode (Plate)
4
Socket-Compatible Tubes ⚠ Not electrically compatible