Abstract
One method of measuring the target capacitance in the photoconductive camera tube is described. The tube is operated in the desk condition and the target capacitance is charged by the scanning beam. Then the electron beam is blanked off during the period of several T. V. fields, while the dark current discharges the target capacitance. The recharging current in the first field after rescanning is measured. The target capacitance can be calculated from the above data. We used the Toshiba 7262A vidicon in the experiment and found that the target capacitance was about 2500 PF.
