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Specialized - Cathode Ray ·CathodeRay

DR75

High-vacuum electrostatic oscilloscope CRT with an approximately 2.5-inch screen and long-persistence phosphor, designed for compact waveform measurement and retained trace display.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
B8G
Base pins
-
Nominal heater
6.3 V / 310 mA

Description

The Mullard DR75 is a high-vacuum electrostatic oscilloscope tube with an approximately 2.5-inch screen and long persistence phosphor.

Socket description

Loctal 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B8G
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
310 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
400 V

Electrostatic focusing/deflection CRT section; electrical/screen/deflection data retained in parameter rows.

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

1951 Mullard Valve and Service Manual

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • Screen Colour / Persistence

    Long persistence

  • Focusing Method

    Electrostatic

  • Deflecting Method

    Double Electrostatic

Other

  • Anode Voltage

    800 V

  • Focusing Electrode Voltage Minimum

    200 V

  • Focusing Electrode Voltage Maximum

    300 V

Data set 02

1957 Philips Receiving and Amplifying Tubes

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Maximum Plate Voltage

    400 V

  • Grid 2 Operating Voltage Minimum

    200 V

  • Grid 2 Operating Voltage Maximum

    300 V

  • Maximum Grid 2 Voltage

    400 V

Characteristic

  • Focusing Method

    Electrostatic

  • Deflection Method

    Double electrostatic

  • Screen Variant

    greenish-yellow, long persistence

Data set 03

1963 Philips Electron Tubes Handbook V2

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • Heater voltage

    6.3 V

    Published heater rating

  • Heater current

    300 mA

    Published heater rating

Capacitance

  • Grid No.1 capacitance

    7 pF

    OscilloscopeCRT

  • D1 plate capacitance

    3 pF

    OscilloscopeCRT

  • D1 prime plate capacitance

    3.3 pF

    OscilloscopeCRT

  • D2 plate capacitance

    2.8 pF

    OscilloscopeCRT

Data set 04

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • Heating: indirect by A.C. or D.C. Ve

    6.3 V

    Published datasheet condition

  • Heizung: indirekt durch Wechsel-~ If

    400 mA

    Published datasheet condition

  • DG 7

    -5 v

    Published datasheet condition

  • Heizung : indirekt ‘durch Wechsel- Ifr

    310 mA

    Published datasheet condition

  • Published value

    3 Ω

    Published datasheet condition

  • Heating : indirect by A.C. or D.C. Ve

    6.3 V

    Published datasheet condition

  • Heizung : indirekt durch Wechsel- If

    310 mA

    Published datasheet condition

  • Chauffage: indirect par C.A. ou C.C. Ve

    6.3 V

    Published datasheet condition

  • Il est recommandé de mettre g

    3 a

    Published datasheet condition

  • Capacitances Cg

    9 pF

    Published datasheet condition

  • Kapazitdten €1

    4.8 pF

    Published datasheet condition

  • Cpi

    4.8 pF

    Published datasheet condition

  • Cp2

    5 pF

    Published datasheet condition

  • Cp21

    5.4 pF

    Published datasheet condition

  • CD1D1*

    0.6 pF

    Published datasheet condition

  • Cp2D2*

    0.8 pF

    Published datasheet condition

  • Cpip1'-D2p2'

    0.1 pF

    Published datasheet condition

  • Dpaisseur de la ligne €¥a‘ - gog ZAg

    0.7 mm

    Published datasheet condition

  • Va2

    800 A

    Published datasheet condition

  • Va1 = 200

    -300 V

    Published datasheet condition

  • Vg = 0

    50 V

    Published datasheet condition

  • Ia2 = 0

    -100 MA

    Published datasheet condition

  • Published value

    0.26 w

    Published datasheet condition

  • N2

    0.16 mm

    Published datasheet condition

  • Va2 = nin

    800 V

    Published datasheet condition

  • vp1D1 p= mBX

    450 V

    Published datasheet condition

  • Vp2p2 'p = BOX

    750 v

    Published datasheet condition

  • 1) Measured on a circle of

    50 mm

    Published datasheet condition

  • Mesuré & un cercle de

    50 mm

    Published datasheet condition

  • Gemessen an einem Xreis von

    50 mm

    Published datasheet condition

  • Cgt

    10 pF

    Published datasheet condition

  • Cgt = 10 pF Cp2»

    4.5 pF

    Published datasheet condition

  • Cpy

    5.3 pF

    Published datasheet condition

  • Cpy = 5,3 pF CDID1!

    0.6 pF

    Published datasheet condition

  • Cpyv

    5.3 pF

    Published datasheet condition

  • Cpyv = 5,3 pF CD2D2'

    0.8 pF

    Published datasheet condition

  • Cpo

    4.5 pF

    Published datasheet condition

  • Cpo = 4,5 pF Cp1Dy'-D2D2'

    0.1 pF

    Published datasheet condition

  • Epaisseur de la ligne (Vg3

    800 V

    Published datasheet condition

  • Vg3

    800 V

    Published datasheet condition

  • Vg2 = 200

    -300 V

    Published datasheet condition

  • Vg1 = 0

    -50 V

    Published datasheet condition

  • N1

    0.25 mm

    Published datasheet condition

  • Gemessen an einem Kreis von

    50 mm

    Published datasheet condition

  • Cg1

    10 pF

    Published datasheet condition

  • Cg1 = 10 pF Cpar

    4.5 pF

    Published datasheet condition

  • Cpy = 5,3 pF Cp1D1

    0.6 pF

    Published datasheet condition

  • Cpyr

    5.3 pF

    Published datasheet condition

  • Cpyr = 5,3 pF Cpgpo

    0.8 pF

    Published datasheet condition

  • Cps

    4.5 pF

    Published datasheet condition

  • Cps = 4,5 pF Cpipyt-D2D2t

    0.15 pF

    Published datasheet condition

  • Epaisseur de la ligne (Vg3 = 800 Vv ¢,

    7 mm

    Published datasheet condition

  • Published value

    0.16 mm

    Published datasheet condition

  • Cgr

    7 PF

    Published datasheet condition

  • Cgr = 7,0 PF Cp2!

    2.8 pF

    Published datasheet condition

  • p1 = 3,0 PP CD1DY!

    0.6 PF

    Published datasheet condition

  • Cpyr

    3.3 PF

    Published datasheet condition

  • Cpyr = 3,3 PF Cpgpar

    0.8 PF

    Published datasheet condition

  • Cpz

    2.8 pF

    Published datasheet condition

  • Epaisseur de la ligne (Vs3

    800 V

    Published datasheet condition

  • VgB

    800 v

    Published datasheet condition

Other

  • Grenzdaten }

    1000 V

    Published datasheet condition

  • Vat

    400 V

    Published datasheet condition

  • ~Vg

    100 V

    Published datasheet condition

  • Wy

    3 mw

    Published datasheet condition

  • Vgy

    1000 V

    Published datasheet condition

  • Vgy = max. 1000 V VD1D1'p = maxX

    450 V

    Published datasheet condition

  • Vg3 =min. 800 V Vpep2'p

    750 V

    Published datasheet condition

  • Vgo

    400 V

    Published datasheet condition

  • Vg1 = max. oV Rp = maxX

    5 MΩ

    Published datasheet condition

  • Vgt

    100 V

    Published datasheet condition

  • Vg3 = max, 1000.V VD1D1'p

    450 V

    Published datasheet condition

  • Vg3 = min. 800 V Vpop2'p

    750 V

    Published datasheet condition

  • Vgo = max. 400V vip

    3 mW

    Published datasheet condition

  • Vg1 = max. ov Rp

    5 MΩ

    Published datasheet condition

  • Vg1

    100 V

    Published datasheet condition

  • Vg3 = max,

    1000 V

    Published datasheet condition

  • Vg3 = min. 800 V Vp2p2'p

    750 V

    Published datasheet condition

  • Vg2

    400 V

    Published datasheet condition

  • Vg2 = max. 400V L4

    3 mW

    Published datasheet condition

  • Vg1 = max,

    100 V

    Published datasheet condition