Description

The General High Voltage CR25 series provide highly regulated outputs for many of the electrodes in a high resolution shadow mask colour CRT. The dc input voltage is 38V (nominal) and the anode output voltage is adjustable between 20kV and 28kV. The output regulator circuits are designed to provide a power supply which has good static and dynamic regulation, combined with very low ripple, ensuring a display that remains stable and sharp over a wide range of brightness modulation. As well as the anode supply, rated at 30 Watts, the module generates adjustable focus G1 and G2 outputs. Current limiting circuits are fitted to protect the outputs against overloads and short circuits. All outputs are individually regulated. Ruggedised military type specification available.

Basic Specification

Input voltage range	34-42V (other voltages may be avaliable – contact factory)
Max. input voltage	45V (unit may be damaged by higher input voltages)
Full load input current	1.3A nominal

Anode Output

Output voltage range	+20kV to +28kV
Output current	1.3mA
Control of output	Internal single turn potentiometer
Output ripple	4.0V peak to peak (at full load, with tube capacitance 2nf)
Line regulation	0.01%
Load regulation	Static: 0.01% (no load to full load)
	Dynamic: 0.1%
Temperature coefficient	200 ppm per °C max. Better temperature coefficients may be specified

Protection

1. Proof against output short circuits and flashovers
2. Output current is limited to approx. 110% of full load current by trip

Focus and grid outputs	Note: The voltages are proportional to the anode voltage setting.
Focus output (adjustable)	4.75kV to 6.0kV. Other voltages upon request. Ripple 0.5V peak to peak max Max. load ±10µA
G1 (grid) output	Fixed output, -200V Max. ripple 0.5V peak to peak. Max. load 3mA