25E5

25E5 is also designated PL36.

The 25E5 is an output pentode intended for use as a line output tube in television receivers, as described in the Rogers datasheet.

Construction

The 25E5 features a coated, unipotential cathode. It has a B7-59 base, a T9 bulb, and uses 8GT basing. The plate is connected to a top cap (C1-2). The tube can be mounted in any position.

Ratings

The Rogers datasheet lists maximum plate voltage as 250 volts, with a maximum plate voltage without current of 550 volts. Maximum positive peak plate voltage is 7000 volts, and maximum negative peak plate voltage is 1500 volts. Maximum grid No.2 voltage is 250 volts, with a maximum grid No.2 voltage without current of 550 volts. Maximum negative peak grid No.1 voltage is 1000 volts. Maximum cathode current is 200 milliamps. Maximum grid No.1 circuit resistance is 0.5 megohm, or 2.2 megohms for line output application. Maximum alternating voltage between cathode and heater is 250 volts (rms). Maximum cathode positive with respect to heater voltage is 250 volts, and maximum cathode negative with respect to heater voltage is 200 volts. Maximum circuit resistance between cathode and heater is 20000 ohms.

Characteristics

At a plate voltage of 100 volts and a grid No.2 voltage of 100 volts, the Rogers datasheet gives typical grid No.1 voltage as -8.2 volts, typical plate current as 100 milliamps, typical grid No.2 current as 7 milliamps, typical transconductance as 14000 micromhos, typical plate resistance as 5000 ohms, and the amplification factor of grid No.2 with respect to grid No.1 as 5.6.

Capacitances

The Rogers datasheet gives grid No.1 to all other elements except plate capacitance as 17.5 µµF, plate to all other elements except grid No.1 capacitance as 8 µµF, and plate to grid No.1 capacitance as a maximum of 1.1 µµF.

Pinout

Pin 1 is an internal connection, pin 2 is the heater, pin 3 is an internal connection, pin 4 is grid No.2, pin 5 is grid No.1, pin 7 is the heater, and pin 8 is the cathode and grid No.3. The heater requires 25 volts at 300 milliamps.

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 25E5, hosted by Frank Philipse's Electron Tube Data sheets.

Documents held here and used to write this page.

• Rogers Electronic Tubes & Components
• Provozní hodnoty: Koncový zesilovač pro horizontální vychylování: (filed under PL36)