6CT7

6CT7 is also designated EAF42.

Description

The 6CT7 is a single diode, remote cut-off R.F. pentode with a coated unipotential cathode, a glass envelope, and an E8-30 base.

Ratings and Characteristics

The 6CT7 has a heater rated at 6.3 volts and 0.2 amps. Maximum ratings for the pentode section include a plate voltage of 300 volts, plate dissipation of 2 watts, Grid No. 2 supply voltage of 550 volts, Grid No. 2 dissipation of 0.3 watts, cathode current of 10 ma, and Grid No. 1 circuit resistance of 3 megohms. The maximum voltage between heater and cathode is 100 volts, and the maximum external resistance between heater and cathode is 20,000 ohms. The diode section has a maximum peak plate voltage of 200 volts and a maximum plate current of 0.8 ma.

Typical operating conditions for the pentode are a plate voltage of 250 volts, Grid No. 2 voltage of 250 volts, plate current of 5.0 ma, Grid No. 2 current of 1.5 ma, and Grid No. 1 voltage of -2.0 volts. Under these conditions, the transconductance is 2,000 µmhos, and the plate resistance is 1.4 megohms. The amplification factor of Grid No. 2 with respect to Grid No. 1 is 18. The Grid No. 1 voltage for a transconductance of 20 µmhos is -43 volts.

Capacitances

Interelectrode capacitances include input capacitance of 4.5 μμF, output capacitance of 5.1 μμF, and plate-to-cathode capacitance of 3.8 μμF. Capacitances between other elements are specified as less than 0.02 μμF (plate to heater), less than 0.0015 μμF (diode plate to Grid No. 1), less than 0.15 μμF (diode plate to pentode plate), less than 0.002 μμF (plate to Grid No. 1), and less than 0.05 μμF (Grid No. 1 to heater).

Mechanical

The 6CT7 has a maximum overall length of 2-3/8" (60mm), a seated height of 2-1/16" (53mm), and a diameter of 7/8" (22mm). It may be mounted in any position.

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.

Original manufacturer datasheets for 6CT7, hosted by Frank Philipse's Electron Tube Data sheets.

Documents held here and used to write this page.

• EAF 42 (EAF 41) Diode-Pentode (filed under EAF42)
• MAXIMUM RATINGS (Design Centre Values)

1 further designation appears alongside 6CT7 in the literature but below the evidence threshold used here, so it is not listed as equivalent.