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Alternatives & variationsDownload PDF datasheet

Specialized - Photo Tube ·PhotoemissiveDetector

R79A

Visitron gas-filled S1 phototube with an extra-large cathode designed for maximum light-beam area in standard theatre projection equipment. Gas amplification increases output for sound and projection sensing.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
-

Description

The Visitron R79 is a tube having an extra large cathode designed for a maximum area of light beam, commonly used in standard theatre projection equipment. A sturdy tube to give constant quality Identical to the R79 series in electrical and four prong base instead of flexible leads. This variant uses the S1 cathode surface described by the family datasheet. The non-V variant has published gas amplification in the family table.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
-
Nominal heater current
-
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

PhotoemissiveDetector

X-ray radiationInterelectrode capacitances
Max plate voltage
90 V

Photoelectric section. Published anode-cathode capacitance approximately 2.5 pF.

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

195X Visitron Rauland

Published operating points and test conditions from this source.

SECTION 1

PhotoemissiveDetector

Other

  • Peak Anode Voltage

    90 V

    Variant-specific maximum rating

  • Anode-Cathode Capacitance

    2.5 pF

    Variant-specific general characteristic

  • Cathode Size [1]

    1.625

    Cathode Size.. ... .. ... .. ... 1.625"x1.125" 1.625"x1.125" 1.625"x1.125" 1.625"x1.125"

  • Cathode Size [2]

    125

    Cathode Size.. ... .. ... .. ... 1.625"x1.125" 1.625"x1.125" 1.625"x1.125" 1.625"x1.125"

  • Cathode Size [3]

    1.625

    Cathode Size.. ... .. ... .. ... 1.625"x1.125" 1.625"x1.125" 1.625"x1.125" 1.625"x1.125"

  • Cathode Size [4]

    125

    Cathode Size.. ... .. ... .. ... 1.625"x1.125" 1.625"x1.125" 1.625"x1.125" 1.625"x1.125"

  • Cathode Size [5]

    1.625

    Cathode Size.. ... .. ... .. ... 1.625"x1.125" 1.625"x1.125" 1.625"x1.125" 1.625"x1.125"

  • Cathode Size [6]

    125

    Cathode Size.. ... .. ... .. ... 1.625"x1.125" 1.625"x1.125" 1.625"x1.125" 1.625"x1.125"

  • Cathode Size [7]

    1.625

    Cathode Size.. ... .. ... .. ... 1.625"x1.125" 1.625"x1.125" 1.625"x1.125" 1.625"x1.125"

  • Cathode Size [8]

    125

    Cathode Size.. ... .. ... .. ... 1.625"x1.125" 1.625"x1.125" 1.625"x1.125" 1.625"x1.125"

  • Capacitance (Anode-Cathode) [1]

    2.5 pF

    Capacitance (Anode-Cathode) ... 2.5 MMF. 2.0 MMF. 2.5 MMF. 2.0 MMF.

  • Capacitance (Anode-Cathode) [2]

    2 pF

    Capacitance (Anode-Cathode) ... 2.5 MMF. 2.0 MMF. 2.5 MMF. 2.0 MMF.

  • Capacitance (Anode-Cathode) [3]

    2.5 pF

    Capacitance (Anode-Cathode) ... 2.5 MMF. 2.0 MMF. 2.5 MMF. 2.0 MMF.

  • Capacitance (Anode-Cathode) [4]

    2 pF

    Capacitance (Anode-Cathode) ... 2.5 MMF. 2.0 MMF. 2.5 MMF. 2.0 MMF.

  • Leakage Resistance (Min) [1]

    1000 Mohm

    Leakage Resistance (Min) . . . . 1000 Meg. 1000 Meg. 1000 Meg. 1000 Meg.

  • Leakage Resistance (Min) [2]

    1000 Mohm

    Leakage Resistance (Min) . . . . 1000 Meg. 1000 Meg. 1000 Meg. 1000 Meg.

  • Leakage Resistance (Min) [3]

    1000 Mohm

    Leakage Resistance (Min) . . . . 1000 Meg. 1000 Meg. 1000 Meg. 1000 Meg.

  • Leakage Resistance (Min) [4]

    1000 Mohm

    Leakage Resistance (Min) . . . . 1000 Meg. 1000 Meg. 1000 Meg. 1000 Meg.

  • Anode Voltage, Peak. oo [1]

    9 V

    Anode Voltage, Peak. oo 9oV SO0V v 500V

  • Anode Voltage, Peak. oo [2]

    500 V

    Anode Voltage, Peak. oo 9oV SO0V v 500V

  • Luminous Sensitivity [1]

    225 V

    Luminous Sensitivity . . ... .. ... .. 225 uwA/L DC 40 uA/L DC 225 uA/L DC 40 vA/L DC

  • Luminous Sensitivity [2]

    40 V

    Luminous Sensitivity . . ... .. ... .. 225 uwA/L DC 40 uA/L DC 225 uA/L DC 40 vA/L DC

  • Luminous Sensitivity [3]

    225 V

    Luminous Sensitivity . . ... .. ... .. 225 uwA/L DC 40 uA/L DC 225 uA/L DC 40 vA/L DC

  • Luminous Sensitivity [4]

    40 V

    Luminous Sensitivity . . ... .. ... .. 225 uwA/L DC 40 uA/L DC 225 uA/L DC 40 vA/L DC

  • Luminous Sensitivity ( [1]

    25 V

    Luminous Sensitivity (25v) .. .. 40 vA/L DC 35 uA/L DC 40 uA/L DC 35 uA/L DC

  • Luminous Sensitivity ( [2]

    40 V

    Luminous Sensitivity (25v) .. .. 40 vA/L DC 35 uA/L DC 40 uA/L DC 35 uA/L DC

  • Luminous Sensitivity ( [3]

    35 V

    Luminous Sensitivity (25v) .. .. 40 vA/L DC 35 uA/L DC 40 uA/L DC 35 uA/L DC

  • Luminous Sensitivity ( [4]

    40 V

    Luminous Sensitivity (25v) .. .. 40 vA/L DC 35 uA/L DC 40 uA/L DC 35 uA/L DC

  • Luminous Sensitivity ( [5]

    35 V

    Luminous Sensitivity (25v) .. .. 40 vA/L DC 35 uA/L DC 40 uA/L DC 35 uA/L DC

  • Gas Amplification [1]

    8

    Gas Amplification .. . . 8 -- - 8 .- -

  • Gas Amplification [2]

    8

    Gas Amplification .. . . 8 -- - 8 .- -

  • Temperature, ambient [1]

    100 C

    Temperature, ambient .. ... . .. 100°C 100°C 100°C 100°C

  • Temperature, ambient [2]

    100 C

    Temperature, ambient .. ... . .. 100°C 100°C 100°C 100°C

  • Temperature, ambient [3]

    100 C

    Temperature, ambient .. ... . .. 100°C 100°C 100°C 100°C

  • Temperature, ambient [4]

    100 C

    Temperature, ambient .. ... . .. 100°C 100°C 100°C 100°C