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Specialized - Cathode Ray ·CathodeRay

5FP4A

Five-inch P4 cathode-ray display tube documented by manufacturer data, using a white short-to-medium-persistence screen with beam focusing and deflection characteristics appropriate to direct visual display.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
65-80
Socket code
IO
Base pins
8
Nominal heater
6.3 V / 600 mA

Description

The Sylvania 5FP4A is a 5-inch direct-view CRT with magnetic focus and deflection, intended for monitor service and using a white screen.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
65-80
Socket code
IO
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

65-80 - 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
Max plate voltage
8000 V

CRT maximum accelerating/anode/ultor voltage is promoted to MaxPlateVoltage; additional electrode ratings, capacitances, operating conditions, deflection/focus and optical data are preserved as parameters.

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

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Deflection method

    Magnetic

  • Focusing method

    Electrostatic

Data set 02

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Heater Voltage

    6.3 V

  • Heater Current

    600 mA

    Nominal; ±10%

  • Focusing Method

    Magnetic text

  • Deflection Method

    Magnetic text

  • Deflection Angle

    53 deg

    Approximate

  • Fluorescence

    White text

  • Persistence

    Medium text

  • Cathode-to-All Capacitance

    5 pF

    Approximate

  • Grid1-to-All Capacitance

    8 pF

    Approximate

  • Phosphorescence

    White text

Other

  • Maximum Anode Voltage

    8800 V

  • Maximum Grid2 Voltage

    450 V

  • Maximum Grid1 Negative Bias

    140 V

  • Maximum Grid1 Positive Peak

    2 V

  • Maximum Heater-Cathode Voltage

    200 V

    EitherPolarity

  • Anode Voltage

    6000 V

  • Grid2 Voltage

    250 V

  • Grid1 Cutoff Voltage Minimum

    -70 V

  • Grid1 Cutoff Voltage Maximum

    -25 V

  • Focusing Coil Current

    120 mA

    Approximate; ±15%

  • Maximum Grid1 Circuit Resistance

    1.5 Mohm

Data set 03

1971 RCA HB3 Binder 1 of 7

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Typical anode voltage

    6000 V

    TypicalOperation

  • Maximum accelerating/anode voltage

    8000 V

  • ANODE VOLTAGE'

    8000 V

    Maximum

  • GRID-No.2 VOLTAGE

    410 V

    Maximum

  • Anode Voltageb

    6000 V

  • Grid—N o.2 Voltage

    250 V

  • Grid—N o.l—Circuit Resistance 1

    5 MΩ

    Maximum

Capacitance

  • Grid 1 to all other electrodes capacitance

    5 pF

    Approximate

  • Cathode to all other electrodes capacitance

    8 pF

    Approximate

Characteristic

  • Deflection angle

    53 degrees

    Approximate

  • Cathode to all other electrodes

    8 pF

  • Grid No.1 to all other electrodes

    5 pF

  • Geflection Angle (Approx.)

    53 degrees