What is the E810F vacuum tube?

The E810F (E810F / 7788) is a pentode vacuum tube designed for preamp / driver applications. Frame-grid. Phenomenal transconductance..

What is a E810F substitute or equivalent?

Direct equivalents to the E810F include 7788. These share the same pinout and operating envelope, so they can usually be swapped without circuit changes — though batch-to-batch variations between manufacturers (NOS vs current production) may shift the sonic character noticeably.

What are the key specifications of the E810F?

Amplification factor μ ≈ 57, transconductance gm ≈ 50 mA/V, plate resistance rp ≈ 42.0 kΩ, max plate voltage 250 V, max plate dissipation 5 W, heater 6.3 V / 0.34 A.

Is the E810F still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the E810F as Sought-after availability. NOS (new-old-stock) examples from RCA, Mullard, Tung-Sol, GE, Sylvania and Telefunken trade among collectors; modern production where it exists comes mostly from JJ Electronic, Electro-Harmonix, Tung-Sol (New Sensor), Genalex, and a handful of small-batch makers.

What does the E810F sound like?

Frame-grid. Phenomenal transconductance.. Sonic character also depends heavily on the circuit operating point, the surrounding tubes in the stage, and the output transformer when present — use the interactive loadline calculator on this page to explore the trade-offs.

By Jean-Michel Falligan Devergne · Reviewed May 29, 2026

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E810F E810F / 7788 Pentode Vacuum Tube

Pentode6.3V / 0.34A9-pin Noval

SourcePhilips·ValvoReviewed2026-05-29StatusDataModelCalcModelunder reviewPDF

Small-signal pentode for low-noise voltage amplification

Datasheet ↗

E810F / 7788 — Philips·Valvo — pentode vacuum tube — (1960)

42.0kΩ

50.0mA/V

14.5pF

0.0pF

3.50pF

GAIN57%

POWER13%

DRIVE58%

LINEARITY72%

SPECIFICATIONS

Heater6.3 V · 0.34 A

Max Plate Voltage250 V

Pa max5 W

Gain Factor57

gm50 mA/V

rp42.0 kΩ

Inter-electrode capacitances

Cgk14.5 pF

Cgp0.036 pF

Cpk3.5 pF

Pinout9-pin Noval

Era1960

RaritySought-after

HEATER6.3V / 0.34A

MAX PLATE250V / 5W

BASEnoval

Source datasheets

3 manufacturer datasheets cross-checked for E810F / 7788

3 verified

EXECUTIVE SUMMARY

The E810F is a indirectly-heated pentode from Philips·Valvo, introduced around 1960. It provides a gain factor (μ) of 57 with 42.0kΩ plate resistance. Commonly used in preamp / driver applications. Frame-grid. Phenomenal transconductance.

HISTORY

Introduced1960ManufacturerPhilips·Valvo

Late Production

E810F Datasheet

Local mirror · PDF

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METRIX TESTER

Test this tube on a Metrix

SPICE model not yet available. Loadline calculator requires calibrated Koren parameters.

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