6EW7

6EW7 has no equivalent designation confirmed by the archive.

The 6EW7 is a twin triode vacuum tube containing two units, designated Unit No. 1 and Unit No. 2, with a unipotential cathode heater designed for 6.3 volts ±10%, AC or DC, at 0.9 amperes.

Construction

The 6EW7 has a maximum overall length of 2.93 inches and a maximum seated length of 2.07 inches. Its bulb diameter is 1.062 inches plus 0 to 1.188 inches, with a JEDEC bulb designation of E9-68. The basing designation for bottom view is 9HF, with pin 1 as the plate of Unit No. 2, pin 2 as the grid of Unit No. 2, pin 3 as the grid of Unit No. 1, pins 4 and 5 as the heater, pin 6 as the plate of Unit No. 1, pin 7 as the grid of Unit No. 1, pin 8 as the cathode of Unit No. 1, and pin 9 as the cathode of Unit No. 2. The tube can operate in any operating position.

Electrical Characteristics

For Unit No. 1, the direct interelectrode capacitances are approximately 4.2 μμf from grid to plate, 2.2 μμf from grid to cathode and heater, and 0.4 μμf from plate to cathode and heater. For Unit No. 2, the corresponding capacitances are approximately 9 μμf, 7 μμf, and 1.2 μμf.

Operating as a Class A amplifier at a plate voltage of 150 volts and a grid voltage of -17.5 volts, Unit No. 1 has an amplification factor of 17.5, a plate resistance of approximately 8750 ohms, a transconductance of 2000 μmhos, and a plate current of 5.5 milliamperes. Under the same conditions, Unit No. 2 has an amplification factor of 6, a plate resistance of approximately 800 ohms, a transconductance of 7500 μmhos, and a plate current of 45 milliamperes.

Additional operating points for Unit No. 2 include a plate current of 95 milliamperes at 60 plate volts and 0 grid volts, and 8 milliamperes at a grid voltage of -25 volts. For Unit No. 1, the grid voltage for a plate current of 10 milliamperes and a plate voltage of 20 volts is approximately -40 volts.

Ratings

Ratings for the 6EW7 are specified for operation in a 525-line, 30-frame television system. For Unit No. 1, the maximum DC plate voltage is 77 volts, the maximum average plate current is 22 milliamperes, and the maximum plate dissipation is 1.5 watts. The maximum peak heater-cathode voltage is 200 volts with the heater either negative or positive with respect to the cathode, and the maximum grid-circuit resistance for grid-resistor-bias or cathode-bias operation is 2.2 megohms.

For Unit No. 2, the maximum DC plate voltage is 77 volts, the maximum peak positive-pulse plate voltage is 1500 volts, the maximum peak negative-pulse grid voltage is 250 volts, the maximum average cathode current is 50 milliamperes, and the maximum plate dissipation is 10 watts. The maximum peak heater-cathode voltage is 200 volts with the heater either negative or positive with respect to the cathode. The datasheet states that the peak heater-cathode voltage rating applies where the duration of the voltage pulse does not exceed 15 per cent of one vertical scanning cycle, which in a 525-line, 30-frame system is 2.5 milliseconds. The DC component of the plate voltage must not exceed 100 volts.

Original manufacturer datasheets for 6EW7, hosted by Frank Philipse's Electron Tube Data sheets.

Documents held here and used to write this page.

• AVERAGE PLATE CHARACTERISTICS Unit No.2