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Specialized - Cathode Ray ·CathodeRay

T979N

English Electric cathode-ray instrument tube with electrostatic beam control and precision deflection, intended for oscillographic or measurement display with screen characteristics designated by type T979N.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
B12F
Socket code
-
Base pins
12
Nominal heater
6.3 V / 300 mA

Description

Five-inch wide-band high-speed oscilloscope cathode-ray tube with electrostatic focus and deflection, post-deflection acceleration, and aluminized screen. N / P2 yellowish-green, medium persistence

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
B12F
Socket code
-
Base pins
12
Nominal heater voltage
6.3 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

B12F - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Cathode Ray

X-ray radiationInterelectrode capacitances

No fixed ratings are recorded for this section.

Maximum final-anode/PDA voltage mapped to MaxPlateVoltage.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1971 English Electric Valve

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Heater voltage

    6.3 V

  • Heater current

    300 mA

  • Maximum anode 4 voltage

    3.3 kV

  • Maximum anode 3/anode 1 voltage

    3.3 kV

  • Maximum anode 2 voltage

    1.5 kV

  • Maximum cathode current

    0.3 mA

  • Maximum deflection electrode voltage

    500 V

  • Typical PDA/screen voltage

    12 kV

Characteristic

  • Screen characteristic

    N / P2 yellowish-green, medium persistence

Capacitance

  • Grid to all other electrodes capacitance

    6.1 pF

  • Cathode to all other electrodes capacitance

    5.7 pF

  • X1 to X2 capacitance

    3.1 pF

  • Y1 to Y2 capacitance

    1.7 pF