GB584726A - Improvements in electrical oscillation generators - Google Patents

Abstract

584,726. Valve generating circuits ; super-regenerative circuits ; relaxation oscillators. MARCONI'S WIRELESS TELEGRAPH CO., Ltd., RUST, N. M., PARTINGTON, G. E., PLAISTOWE, D. L., and FEWINGS, D. J. Feb. 4, 1941, No. 1480. [Class 40 (v)] A valve is arranged to operate both as a radio-frequency oscillator and as a blocking pulse generator, so that pulses of radio-frequency energy are produced. The circuit is employed for transmission and/or for superregenerative reception. As shown in Fig. 1, the radio-frequency circuit comprises a Lecher pair TL connected to the grid and anode of a valve T, and the pulse is produced by a transformer TR coupling the grid and plate circuits, its frequency being determined by a resistance and capacity in the cathode leg. Chokes CH2, CH3 keep the radio frequency from the transformer TR. In Fig. 4 an auto-transformer AT is used for the pulse generator, and signal voltage is applied at a transformer TR1, in the anode circuit. The signal voltage may produce amplitude or frequency modulation of the pulses, and the same circuit may be used for reception of signals sent by a similar transmitter, anode voltage is reduced, the receiving instrument being associated with the transformer TR1. The circuit may also be used as a super-regenerative receiver of waves sent from a normal transmitter. Normal tuned circuits may be used instead of the Lecher pairs, and two valves may be connected to such tuned circuit in push-pull relation, (Fig. 5 not shown). The line pair TL may have a condenser across its outer end of capacity equal to that between anode and grid, the pulse transformer then being connected to the mid-points of the line.