GB492276A - Television receiver - Google Patents

Abstract

492,276. Television; cathode -ray tubes. RADIOAKT.-GES. D. S. LOEWE. March 16, 1937, No. 7679. Convention date, March 21, 1936. [Classes 39 (i), 40 (iii), and 40 (v)] The anode 3 and deflecting plates 6 of a cathode-ray tube are at a high positive potential 1, which is also used for the associated relaxation oscillator 9, 10, 11, and are connected together through a leakage resistance 8, the cathode of 2 the tube and the relaxation oscillator are earthed, and a high voltage condenser 7 couples the deflecting plate to the oscillator. When the coupling transmits all the frequencies equally well, the available output from the oscillator is made large compared with the consumption of the leakage resistance by making the resistance 10 smaller than the resistance 8. Otherwise the coupling is designed to transmit the lower frequencies better than the higher by tapping the output from the series resistance 10, Fig. 2 (not shown), or by using a low-pass resistance-capacity filter, Fig. 3 (not shown). Alternatively, the deflecting plates are screened from the cathode ray by reticulated grids, which are connected to the anode 3, and the deflecting plates are biassed negatively relatively to the anode to prevent electronic current reaching the plates, Fig. 4 (not shown). It is then possible to deflect the ray without absorption of power, and the leakage resistance can be of such size that the relaxation oscillator is not appreciably loaded by the capacity of the circuit of the plates.