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Specialized - Cathode Ray ·CathodeRay

3MP1

Three-inch cathode-ray tube for oscilloscope and instrument display service, using electrostatic focusing and electrostatic deflection. Its P1 screen designation identifies the phosphor variant within this compact oscillographic family.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
B12A
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

Three-inch direct-view oscilloscope CRT with electrostatic focus and electrostatic deflection.

Socket description

Duodecal 12-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B12A
Base pins
-
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

No fixed ratings are recorded for this section.

CRT section; maximum anode voltage 2750 V and capacitances retained in parameter table.

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 General Electric Transmitting Types

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Focusing method

    Electrostatic

  • Deflection method

    Electrostatic

  • Phosphor

    P1

Data set 02

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • Phosphor

    P1

  • Focusing Method

    Electrostatic

  • Deflecting Method

    Electrostatic

Other

  • Maximum Anode No. 2 Voltage

    2750 V

  • Typical Anode No. 2 Voltage

    2000 V

Data set 03

1960 Waterman Products

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • RAYONIC®

    3

    RAYONIC® 3MP1 CATHODE RAY TUBE

  • Heater VOltage ..vrcmeecrnmmmnnssimssonion e

    3 mm

    Heater VOltage ..vrcmeecrnmmmnnssimssonion e 003 VOIS

  • Heater Current ... s [1]

    600 mA

    Heater Current ... s 0.6 +=10% Amperes

  • Heater Current ... s [2]

    10 A

    Heater Current ... s 0.6 +=10% Amperes

  • Cathode to all other electrodes ..o

    7.5

    Cathode to all other electrodes ..o 7.5 upf

  • Grid # [1]

    1 pF

    Grid #1 to all other electrodes ... 8.0 ppf

  • Grid # [2]

    8 pF

    Grid #1 to all other electrodes ... 8.0 ppf

  • Minimum Useful Screen DIameter

    2 in

    Minimum Useful Screen DIameter ... 2% Inches

  • Positive voltage on D1 deflects beam approximately toward pin #

    4

    Positive voltage on D1 deflects beam approximately toward pin #4

  • Positive voltage on D3 deflects beam approximately toward pin #

    1

    Positive voltage on D3 deflects beam approximately toward pin #1

  • Anode Voltage (A2)

    2190

    Anode Voltage (A2) .. 2190 VOIEs DC

  • Anode (A2) Input ..o

    6

    Anode (A2) Input ..o . 6 Watts

  • Anode = [1]

    1 V

    Anode =1 (Focusing Electrode) Voltage ... .. 1000 Volts

  • Anode = [2]

    1000 V

    Anode =1 (Focusing Electrode) Voltage ... .. 1000 Volts

  • Grid

    41

    Grid 41 (G1) Voltage

  • Heater positive with respect to cathode ... T

    125 V

    Heater positive with respect to cathode ... T 125 Volts

  • Peak Voltage between Anode # [1]

    2 V

    Peak Voltage between Anode #2 and any deflecting Plate i 500 Volts

  • Peak Voltage between Anode # [2]

    500 V

    Peak Voltage between Anode #2 and any deflecting Plate i 500 Volts

  • Focusing Electrode (A1) Current for any operating condition [1]

    -15 A

    Focusing Electrode (A1) Current for any operating condition ... —15t0 +10 pAmps

  • Focusing Electrode (A1) Current for any operating condition [2]

    10 A

    Focusing Electrode (A1) Current for any operating condition ... —15t0 +10 pAmps

  • Spot Position (Undeflected) (Note [1]

    1 mm

    Spot Position (Undeflected) (Note 1) 15 Max. mm

  • Spot Position (Undeflected) (Note [2]

    15 mm

    Spot Position (Undeflected) (Note 1) 15 Max. mm

  • Al Voltage [1]

    12

    Al Voltage 12% to 30% of A2 Voltage

  • Al Voltage [2]

    30

    Al Voltage 12% to 30% of A2 Voltage

  • G1 Voltage [1]

    2.7

    G1 Voltage 2.7% to 6.3% of A2 Voltage (Note 2)

  • G1 Voltage [2]

    6.3

    G1 Voltage 2.7% to 6.3% of A2 Voltage (Note 2)

  • G1 Voltage [3]

    2

    G1 Voltage 2.7% to 6.3% of A2 Voltage (Note 2)

  • Anode Voltage (A2) [1]

    500 V

    Anode Voltage (A2) 500 1000 2000 Volts

  • Anode Voltage (A2) [2]

    1000 V

    Anode Voltage (A2) 500 1000 2000 Volts

  • Anode Voltage (A2) [3]

    2000 V

    Anode Voltage (A2) 500 1000 2000 Volts

  • Focusing Electrode Voltage (A1) [1]

    60 V

    Focusing Electrode Voltage (A1) 60 to 150 120 to 300 240 to 600 | Volts

  • Focusing Electrode Voltage (A1) [2]

    150 V

    Focusing Electrode Voltage (A1) 60 to 150 120 to 300 240 to 600 | Volts

  • Focusing Electrode Voltage (A1) [3]

    120 V

    Focusing Electrode Voltage (A1) 60 to 150 120 to 300 240 to 600 | Volts

  • Focusing Electrode Voltage (A1) [4]

    300 V

    Focusing Electrode Voltage (A1) 60 to 150 120 to 300 240 to 600 | Volts

  • Focusing Electrode Voltage (A1) [5]

    240 V

    Focusing Electrode Voltage (A1) 60 to 150 120 to 300 240 to 600 | Volts

  • Focusing Electrode Voltage (A1) [6]

    600 V

    Focusing Electrode Voltage (A1) 60 to 150 120 to 300 240 to 600 | Volts

  • Grid # [1]

    1 V

    Grid #1 Voltage (Note 2) ~13.5t0 -31.5 [—27to —63 | —54to —126| Volts

  • Grid # [2]

    2 V

    Grid #1 Voltage (Note 2) ~13.5t0 -31.5 [—27to —63 | —54to —126| Volts

  • Grid # [3]

    13.5 V

    Grid #1 Voltage (Note 2) ~13.5t0 -31.5 [—27to —63 | —54to —126| Volts

  • Grid # [4]

    -31.5 V

    Grid #1 Voltage (Note 2) ~13.5t0 -31.5 [—27to —63 | —54to —126| Volts

  • Grid # [5]

    -27 V

    Grid #1 Voltage (Note 2) ~13.5t0 -31.5 [—27to —63 | —54to —126| Volts

  • Grid # [6]

    -63 V

    Grid #1 Voltage (Note 2) ~13.5t0 -31.5 [—27to —63 | —54to —126| Volts

  • Grid # [7]

    -54 V

    Grid #1 Voltage (Note 2) ~13.5t0 -31.5 [—27to —63 | —54to —126| Volts

  • Grid # [8]

    -126 V

    Grid #1 Voltage (Note 2) ~13.5t0 -31.5 [—27to —63 | —54to —126| Volts

  • Deflection Factor D1-D2 [1]

    57.51072 V

    Deflection Factor D1-D2 57.51072.5 115to0 145 23010290 | Volts DC/Inch

  • Deflection Factor D1-D2 [2]

    5 V

    Deflection Factor D1-D2 57.51072.5 115to0 145 23010290 | Volts DC/Inch

  • Deflection Factor D1-D2 [3]

    115 V

    Deflection Factor D1-D2 57.51072.5 115to0 145 23010290 | Volts DC/Inch

  • Deflection Factor D1-D2 [4]

    145 V

    Deflection Factor D1-D2 57.51072.5 115to0 145 23010290 | Volts DC/Inch

  • Deflection Factor D1-D2 [5]

    23010290 V

    Deflection Factor D1-D2 57.51072.5 115to0 145 23010290 | Volts DC/Inch

  • Deflection Factor D3-D4 [1]

    55 V

    Deflection Factor D3-D4 55t0 70 i10to 140 220to 280 | Volts DC/Inch

  • Deflection Factor D3-D4 [2]

    70 V

    Deflection Factor D3-D4 55t0 70 i10to 140 220to 280 | Volts DC/Inch

  • Deflection Factor D3-D4 [3]

    0 V

    Deflection Factor D3-D4 55t0 70 i10to 140 220to 280 | Volts DC/Inch

  • Deflection Factor D3-D4 [4]

    140 V

    Deflection Factor D3-D4 55t0 70 i10to 140 220to 280 | Volts DC/Inch

  • Deflection Factor D3-D4 [5]

    220 V

    Deflection Factor D3-D4 55t0 70 i10to 140 220to 280 | Volts DC/Inch

  • Deflection Factor D3-D4 [6]

    280 V

    Deflection Factor D3-D4 55t0 70 i10to 140 220to 280 | Volts DC/Inch

  • Grid # [1]

    1

    Grid #1 Circuit Resistance . 1.5 Megohms

  • Grid # [2]

    1.5

    Grid #1 Circuit Resistance . 1.5 Megohms

  • Resistance in any Deflecting Electrode Circuit (NOte [1]

    3 mm

    Resistance in any Deflecting Electrode Circuit (NOte 3) wcrmcrssmmessmns 1.0 Megohms

  • Resistance in any Deflecting Electrode Circuit (NOte [2]

    1 mm

    Resistance in any Deflecting Electrode Circuit (NOte 3) wcrmcrssmmessmns 1.0 Megohms

  • Published value

    1

    1. With deflecting electrodes connected to Anode (A2).

  • Published value

    2

    2. For visual extinction of undeflected focused spot.

  • Published value

    3

    3. The resistance in each deflecting electrode circuit should be approximately equal.

  • fiuorescent, yellow phosphorescent, long persistence phosphor. Use of

    3

    fiuorescent, yellow phosphorescent, long persistence phosphor. Use of 3MP7 at anode voltages below

Data set 04

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Focusing method

    1 code

    Electrostatic

  • Deflection method

    1 code

    Electrostatic

  • Deflection factor D1-D2 minimum

    230 V/in

  • Deflection factor D1-D2 maximum

    290 V/in

  • Deflection factor D3-D4 minimum

    220 V/in

  • Deflection factor D3-D4 maximum

    280 V/in

  • Useful screen / scan

    1 code

    2.75 in minimum useful screen diameter

Other

  • Anode No. 2 / accelerator voltage maximum

    2750 V

  • Anode No. 2 / accelerator voltage

    2000 V

  • Focusing electrode voltage maximum

    1100 V

  • Focusing electrode voltage minimum

    400 V

  • Focusing electrode voltage maximum

    700 V

  • Grid No. 1 cutoff voltage minimum

    -126 V

  • Grid No. 1 cutoff voltage maximum

    0 V

  • Peak heater-to-cathode voltage

    140 V

  • Peak voltage between accelerator and any deflection plate

    550 V

  • Grid No. 1 negative bias maximum

    220 V

  • Grid No. 1 circuit resistance maximum

    1.5 MOhm

  • Deflection circuit resistance maximum

    5 MOhm

Capacitance

  • Cathode to all other electrodes

    2.2 pF

    Approximate or published bound

  • Grid No. 1 to all other electrodes

    10.3 pF

    Approximate or published bound

  • Deflection plates 1-2 capacitance

    1.3 pF

    Approximate or published bound

  • Deflection plates 3-4 capacitance

    1.2 pF

    Approximate or published bound