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Specialized - Cathode Ray ·CathodeRay

908

High-vacuum cathode-ray tube with electrostatic focusing and deflection and a bluish, extremely short-persistence screen. Its rapid decay and direct electrostatic beam control suit oscillographic measurement and transient display.

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

Description

Rsflf’% Pefi”? -@J March 21 1945 - 908- 'i'f-: HIGH-VACUUM CATHODE-RAY TUBE ‘General: Heater, for Unipotential Cathode R Voltage. « + 4+ = « & o 2.5%10% . .. . a or dc volts Current. v « v v o oo v 21 o ioe e oo .. am. Direct Interelectrode Capacitances: ‘ : . Grid to All Qther Electrodes. . . « . . 9.0 .. upf DJq to All Other Electrodes. .+ . . .. 85 .. pf - DJ3 to A1l Other Electrodes. « & « .o 6.5 . . upf PhosPhOr « . « «-v s s o w oo o o ¢ s a s o o oo No. b Fluorescence « . = v ¢ o o & o« & e e e s« « o Bluish Persistence. « « « « ¢ « & ;<Br|ghtness negllglble in . less than 30 microseconds Focusing Method. « + v « « o v & Electrostatic De

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

Cathode Ray

X-ray radiationInterelectrode capacitances

No fixed ratings are recorded for this section.

Source-derived section; identical dual beam-power sections compressed where applicable.

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

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Voltage. « +

    10 V

    Voltage. « + 4+ = « & o 2.5%10% . .. . a or dc volts

  • Grid to All Qther Electrodes. . . «

    9 pF

    Grid to All Qther Electrodes. . . « . . 9.0 .. upf

  • DJq to All Other Electrodes. .+

    85 pF

    DJq to All Other Electrodes. .+ . . .. 85 .. pf -

  • DJ3 to A1l Other Electrodes. « & « .o

    6.5 pF

    DJ3 to A1l Other Electrodes. « & « .o 6.5 . . upf

  • less than

    30 s

    . less than 30 microseconds

  • ANODE No

    1650 V

    . ANODE No.2 VOLTAGE. + v v = 4w o o o « » 1650 max. volts’

  • ANODE No

    1 V

    - ANODE No.1 VOLTAGE . + v v & « & o &« "«

  • . 1100 max. volts

    1100 V

    . 1100 max. volts

  • PEAK VOLTAGE BETWEEN ANODE No

    2 V

    PEAK VOLTAGE BETWEEN ANODE No.2 and e S :

  • ANY DEFLECTING ELECTRODE

    660 V

    : ANY DEFLECTING ELECTRODE . 660 max. volts

  • Anode No

    1500 V

    Anode No.2 Voltage™®. . .. . . .. 1000 1500 . .. volts -

  • Anode No

    4 V

    .Anode No.1 Voltage for.Focus at 4 T

  • 75% of Grid Voltage for Cutoff® 285. 430-approx,volts

    430 V

    75% of Grid Voltage for Cutoff® 285. 430-approx,volts

  • Grid Voltage for Visual Cutoff#

    -50 V

    Grid Voltage for Visual Cutoff#. . -33 . -50 . .. volts

  • Max. Anode No

    1330 A

    . Max. Anode No.1 Current™. . ... ~—. 1330 -microamp..-

  • * Brilliance and definition decrease wuth decreasing anode No

    2 V

    * Brilliance and definition decrease wuth decreasing anode No.2 voltage.

  • in general, anode No

    1000 V

    in general, anode No.2 voltage should not be less than 1000 volts. ’

  • * Under conditions with anode No

    1500 V

    * Under conditions with anode No.2 volts =1500, anode No.l volts adJusted A

  • for focus, and grid volts =

    0 V

    for focus, and grid volts =0, )

  • able test conditions are: anode No

    1500 V

    able test conditions are: anode No.2 voltage, 1500 volts; ~

  • resistors, | megohm each, connected to anode No

    2 ohm

    resistors, | megohm each, connected to anode No.2; the tube

  • Grid-Circuit Impedance. . « . «

    1.5 ohm

    Grid-Circuit Impedance. . « . « . . . . . 1.5 max. mégohmsf'f:*

  • Circuit at Heater-Supply Frequency

    1 ohm

    Circuit at Heater-Supply Frequency 1.0 max. megohm-

  • Electrode. Circuit

    5 ohm

    Electrode. Circuit . 5.0 max. megohms™~ . .

  • H Eg

    1 V

    H Eg 2.5 VOLTS 1 IAENNNERE AR R

  • FOCUSING ELECTRODE (ANODE N2

    1 V

    FOCUSING ELECTRODE (ANODE N21) VOLTS