6085

6085 is also designated E80CC. Completed sales put the typical price at $55.04 per tube.

Description

The 6085 is a special quality double triode designed for use as an A.F. and D.C. amplifier, as described in the Philips datasheet. It has a noval base with gold plated pins.

Construction and Heater

The 6085 has indirect heating and can be operated on A.C. or D.C., with series or parallel supply. The heater can be operated at 6.3 V or 12.6 V, drawing 0.6 A at 6.3 V and 0.3 A at 12.6 V. The heater current tolerance is 285 to 315 mA at 12.6 V.

Ratings

The maximum anode voltage is 300 V, and the maximum plate voltage without current is 550 V. The maximum plate dissipation is 1.5 watts per system, with a maximum anode dissipation of 2 W. The maximum negative grid bias is 200 volts, and the maximum grid circuit resistance is 2 megohms. The maximum cathode current is 10 mA, with a peak value of 150 mA, and the maximum grid current peak value is 30 mA. The maximum voltage between heater and cathode is 60 volts (with a maximum of 120 V between cathode and heater per another rating), and the maximum external resistance between heater and cathode is 20,000 ohms. The maximum bulb temperature is 170 °C.

Characteristics

Typical characteristics per system at 250 V plate voltage and -5.5 V grid voltage include a plate current of 6 mA and a transconductance of 2700 micromhos. The typical amplification factor is 27, and the typical internal resistance is 10 kΩ. The maximum cut-off voltage is -17 V.

Special Quality and Testing

The 6085 is designed to have low interface resistance after long periods of operation under cut-off conditions and is shock and vibration resistant. It is tested for mechanical quality with an NRL shock machine at 500 g acceleration and at a vibration frequency of 50 Hz at 2.5 g acceleration. The tube is rated for a life test of 10000 hours, tested at a heater voltage of 6.3 V, anode voltage of 250 V, and a cathode resistor of 920 Ω. The typical cathode heating time is 16 seconds, with a maximum of 23 seconds, and the minimum cathode cooling time is 13 seconds.

Electrical Limits and Capacitances

The maximum leakage current between cathode and heater at 120 V is 12 μA. The maximum negative grid current is 0.5 μA initially and 1.0 μA at end of life. The maximum difference in anode current of two sections is 3.0 mA. Capacitance limits include a maximum grid to heater capacitance of 0.23 pF, a maximum plate to plate capacitance between systems I and II of 0.8 μμF, and a maximum grid to plate capacitance for triode system II of 2.75 μμF. The maximum grid to heater capacitance for triode system II is 0.2 μμF. The maximum anode to anode other section capacitance is 1.3 pF without external screen, the maximum grid to grid other section capacitance is 13 mpF, the maximum anode to grid other section capacitance is 0.1 pF, and the maximum grid to anode other section capacitance is 65 mpF.

Equivalence is asserted only where the archive's own literature states it directly, in at least 40 separate documents. Tubes that merely substitute in some circuits are not listed here.

Base B9A, viewed from below (the wiring side), pins numbered clockwise from the key. Read from the datasheet's basing table and checked against it automatically — confirm against the original datasheet before wiring.

Per-tube prices from completed sales, 2026-06-27 to 2026-09-12. Matched pairs and quads are divided out. See the price index for how these move over time.

Original manufacturer datasheets for 6085, hosted by Frank Philipse's Electron Tube Data sheets.

Documents held here and used to write this page.

• ## **PHILIPS**
• S.Q. TUBE (filed under E80CC)