E810F — Small Signal Pentode, Noval | Tubeofile

E810F

Small Signal Pentode — Noval

Philips

Known Equivalents & Substitutes

7788CV5809

Similar Tubes (Not Drop-In Compatible)

E282F

Philips frame-grid pentode in same family — listed as equivalent by Brans but different pinout (Magnoval base), not pin-for-pin compatible

Philips pentode listed as equivalent by Brans — different heater voltage (P-series = 300 mA series heater), not pin-for-pin compatible

Electrical Specifications

Section 1 — Pentode

Absolute Maximum

Anode Voltage (max)Anode Voltage (max)250V

Screen Voltage (max)Screen Voltage (max)200V

Anode Dissipation (max)Anode Dissipation (max)5W

Screen Dissipation (max)Screen Dissipation (max)1W

Cathode Current (max)Cathode Current (max)

Section 2 — Triode Strapped (estimated)

Absolute Maximum

Anode Voltage (max)Anode Voltage (max, limited by Vs_max)200V

Anode Dissipation (max)Anode Dissipation (max)5W

Cathode Current (max)Cathode Current (max)50mA

Typical Operating

Anode ResistanceAnode Resistance (estimated, μ/gm)1,140Ω

Heater

Heater VoltageHeater Voltage6.3V

Heater CurrentHeater Current0.34A

Notes

SQ (Special Quality) designation indicates tighter parameter tolerances, longer rated life, and enhanced mechanical ruggedness compared to standard production valves.
Frame-grid construction: the control grid uses a precision-wound frame grid giving very high and consistent transconductance. Two g1 pins (4 and 5) are provided for low-inductance grid connection at VHF.
Suppressor grid (g3, pin 9) is internally connected to the cathode.
The datasheet specifies the anode supply voltage (Vba) rather than anode voltage (Va) directly; at the recommended operating point (Vba=135V, Rk=360Ω, Ia=35mA), the actual anode voltage is approximately 135 - (35 × 0.360) = 122V.
Heater current: Philips datasheet specifies 340 mA (Column I). Radiomuseum lists 0.34 A. End-of-life range (Column III) is 320-360 mA.
Triode-strapped estimates: mu ≈ 57 (from datasheet amplification factor g2/g1), gm ≈ 50 mA/V, ra ≈ 1140 Ω. No manufacturer triode-strapped data exists; these are derived from pentode parameters. Not in Schlangen's triode-strapped reference.
Philips datasheet 722 1337-1341, dated 8.8.1962, marked 'Tentative data'.
Rg1_max depends on bias method: 0.2 MΩ (fixed bias), 0.6 MΩ (Rk=47Ω), 3.5 MΩ (Rk=360Ω).

Pin Layout — Noval

1Internal Connection (shield)

2Heater

3Heater

References