3AP1A
Electrostatic CRT
Source ........................................ Sylvania - 1959
Bulb .......................................... J24C
Base Type ..................................... Medium 7-Pin (A7-13)
Maximum Overall Height ........................ 11-1/2 In.
Maximum Diameter .............................. 3 In.
EIA Base ...................................... 7CE
Minimum Useful Screen Diameter ................ 2-3/4 In.
Focusing Method ............................... Sylvania - 1959
Deflecting Method ............................. Electrostatic
Deflecting Angle (approx) ..................... Electrostatic Deg.
Fluorescence ............................... P1
Phosphorescence ............................ Green
Faceplate ..................................... Medium
Grid to All Other ............................. 9 pf
D1 to All Others .............................. 8.5 pf
Anode No. 2 Voltage ........................... 1650 V
Grid Voltage
Negative Bias Value ........................ 125 V
Positive Bias Voltage ...................... 0 V
Peak Voltage Between Anode No. 2 and
Any Deflection Plate ....................... 550 V
Grid Circuit Resistance ....................... 1.5M Ω
Deflection Circuit Resistance ................. 5.0M Ω
Characteristics and Typical Operation
Anode No. 1 Voltage ........................... 240 to 560 V
Grid No. 1 Voltage Required for Cutoff ........ -25 to -75 V
Deflection Factor
Deflecting Plates No. 1 & 2 ................... 90 to 137 V/In
Anode No. 1 Voltage ........................... 285 V
Grid No. 1 Voltage Required for Cutoff ........ -33 V
Deflecting Plates No. 1 & 2 ................... 77 V/In
Deflecting Plates No. 3 & 4 ................... 72.5 V/In
1. With D2 positive with respect to D1, the spot is deflected toward pin 1. With D4 positive with respect to D3, the spot is deflected toward pin 6.
2. Brillance and definition decrease with decreasing Anode No. 2 Voltage. In general, Anode No. 2 voltage should not be less than 1000 volts.
3. Visual extinction of undeflected spot.
4. The plane through the tube axis and Pin 6 may vary from the trace produced by Deflecting Plates 3-4 by an angular tolerance measured about the tube axis; of 10 degrees.
5. Angle between D1-D2 trace and D3-D4 trace is 90 degrees +/- 3 degrees.
6. Deflecting Plates 1-2 are nearer the screen.
7. Deflecting Plates 3-4 are nearer the base.