
Tube-number record
EL50
2 archive entries
ClassAmplifier Pentode
Filament6.3 V @ 1.35 mA
Construction
Primary TypePentode
EnvelopeGlass with top cap
Sections1
Filament / Heater
Heater NotesIndirect, AC, Parallel
Absolute Maximum Ratings
Plate Voltage800 V
Plate Dissipation18 W
Grid 2 Voltage425 V
Audio Performance
Typical THD6.6%
Power Output84 W
Key Features
- Top-cap anode connection
- High power push-pull capability
- Indirectly heated cathode
Typical Operation
| Mode | Plate V | Gm (µmhos) | Rp (Ω) | µ | Plate mA |
|---|---|---|---|---|---|
| Static (400V) | 400 V | 6000 | 30000 | — | 45 mA |
| Static (800V) | 800 V | 4000 | 50000 | — | 22.5 mA |
| Class A/B Balans (Fixed Bias) | 800 V | — | — | — | 30 mA |
Application Notes
Two tubes in Class A/B push-pull can deliver up to 84W at 800V plate voltage. The anode connection on the bulb allows for high voltage without special measures.
Datasheets
Datasheet: EL50.pdf
Download PDFLoading datasheet...
Datasheets courtesy of Frank Philipse via Frank's Electron Tube Data Sheets.





