6DJ8 — Small Signal Triode, Noval | Tubeofile

6DJ8

Small Signal Triode — Noval

Known Equivalents & Substitutes

ECC88 6922E88CCCCaCV2492CV53586N23P6N23P-EV7308E188CCECC804

Similar Tubes (Not Drop-In Compatible)

ECC81

Noval double triode with same pinout but higher mu (60), lower gm (5.5 mA/V), higher ra (10900 Ω) — designed for higher Va operation

Noval double triode for VHF/FM tuners but different characteristics (mu=58, gm=6.2 mA/V) and different pinout — not pin-compatible

PCC88

Series-string version with 7V/0.3A heater — identical characteristics otherwise but not a drop-in replacement due to different heater voltage

Electrical Specifications

Absolute Maximum

Anode Voltage (max)Anode Voltage (max)130V

Anode Dissipation (max)Anode Dissipation (max per section)1.8W

Cathode Current (max)Cathode Current (max per section)25mA

Heater-to-Cathode Voltage (max)Heater-to-Cathode Voltage (max)150V

Notes

The 6DJ8 is the RETMA (American) designation for the Philips/Mullard ECC88. Electrically and physically identical — pin-for-pin drop-in replacement.
The 6922/E88CC is the special-quality long-life version with tighter tolerances and 10,000-hour rated life.
7308/E188CC is an even higher reliability grade — can substitute for 6DJ8 but not vice versa in critical applications.
CCa is the Telefunken premium-grade designation for the E88CC/6922.
Max anode voltage is only 130V (DC component) — much lower than conventional dual triodes like ECC81 (300V). This is a low-voltage tube.
Fixed grid bias is only permitted when Ia <= 5 mA. For normal operating currents, cathode bias (self-bias) is required.
Max Pa is 1.8 W per section, Ik max is 25 mA per section.
Pin 9 is an internal shield between the two triode sections.

Pin Layout — Noval

1Anode (triode 2)

2Grid (triode 2)

3Cathode (triode 2)

Socket-Compatible Tubes ⚠ Not electrically compatible

References