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Specialized - Cathode Ray ·CathodeRay

5FP7A

Five-inch P7 cathode-ray instrument tube for oscillograph or measurement display, with manufacturer-specified focusing, deflection, accelerating voltages, and phosphor characteristics for precision waveform presentation.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
DUODECAL11
Base pins
8
Nominal heater
6.3 V / 600 mA

Description

The Sylvania 5FP7A is a 5-inch direct-view CRT with magnetic focus and deflection, intended for radarindicator service and using a blue-white screen.

Socket description

Duodecal 11-contact CRT base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
DUODECAL11
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

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

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

    Blue-White text

  • Persistence

    Long text

  • Cathode-to-All Capacitance

    5 pF

    Approximate

  • Grid1-to-All Capacitance

    8 pF

    Approximate

  • Phosphorescence

    Yellow text

Other

  • Maximum Anode Voltage

    8800 V

  • Maximum Grid2 Voltage

    770 V

  • Maximum Grid1 Negative Bias

    200 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 02

1971 RCA HB3 Binder 1 of 7

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Peak heater-cathode voltage

    125 V

    HeaterNegative

  • Peak heater-cathode voltage

    125 V

    HeaterPositive

  • Typical anode voltage low

    4000 V

    TypicalOperationLow

  • Typical anode voltage high

    7000 V

    TypicalOperationHigh

  • Maximum accelerating/anode voltage

    8000 V

  • ANODE VOLTAGE

    8000 V

    Maximum

  • GRID-No.~ VOLTAGE

    700 V

    Maximum

  • PEAK GRID-No.l DRIVE FROM CUTOFF

    65 V

    Maximum

  • Anode Voltage" 4000

    7000 V

  • Grid-No.2 Voltage 250

    250 V

  • Grid-No.l Voltage° -25 to -70

    -25 to -70 V

  • Grid-No.2 Current -15 to +15 -15 tc

    15 uA

  • Grid-No.l-Circuit Resistance

    1.5 MΩ

    Maximum

Capacitance

  • Grid 1 to all other electrodes capacitance

    8 pF

    Approximate

  • Cathode to all other electrodes capacitance

    5 pF

    Approximate

Characteristic

  • Deflection angle

    53 degrees

    Approximate

  • Current

    600 mA

  • Deflection angle

    53 degrees

    Approximate