Specialized - Cathode Ray ·CathodeRay
Small electrostatically focused and deflected P2 cathode-ray tube for oscilloscope and precision-instrument display, with post-deflection acceleration and a 6.3 V heater.
The Du Mont 3ACP2A is a tight-tolerance flat-face single-beam CRT using post-acceleration for high light output, sensitivity, and small spot size. This variant uses a P2 screen with blue-green/green fluorescence and long persistence.
Large readout/Nixie 14-contact base, 44.5 mm pin circle
General specifications
Properties common to every published source and operating point.
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
1 physical section, each with unique specifications.
Section 1
Published ratings and characteristics promoted where clearly stated.
Source-dependent data
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 01
Published operating points and test conditions from this source.
Heater or filament voltage
6.3 V
Published nominal value
Heater or filament current
600 mA
Published nominal value
Deflection factor D1-D2
175 to 205 V/in
Published typical operation
Deflection factor D3-D4
138 to 158 V/in
Published typical operation
Maximum anode voltage
6000 V
Published maximum or peak rating
Data set 02
Published operating points and test conditions from this source.
Heater Voltage
6.3 V
Heater Current
600 mA
Focusing Method
Electrostatic text
Deflection Method
Electrostatic text
Phosphor
P2 text
Fluorescence
Blue-green/green text
Persistence
Long text
Post-Acceleration
Present text
Data set 03
Published operating points and test conditions from this source.
Focusing method
Electrostatic
Deflection method
Electrostatic
Heater voltage
6.3 V
Heater current
600 mA
Fluorescence
Blue-green
Post-deflection acceleration
Present
Application
Oscilloscope / precision instrument display
Typical anode-2 voltage
2000 V
Focus voltage range
390 to 550 V
Grid cutoff voltage range
-45 to -75 V
Anode-2 voltage maximum
3000 V