GB639984A - Improvements in or relating to electronic oscillator devices - Google Patents

Abstract

639,984. Velocity -- modulated tubes. STEVENS, A. H. (Leland Stanford Junior University, Board of Trustees of). May 13, 1942, No. 16882/44. Divided out of 639,981. [A Specification was laid open to inspection under Sect. 91 of the Acts, June 19, 1946.] [Class 39 (i)] [Also in Group XL (c)] A velocity-modulated cavity-resonator tube is used as a super-regenerative detector. In one form, Fig. 1 (not shown), the quenching signals are applied to either or both of (1) a modulating grid in front of the cathode, or (2) a tubular electrode in the drift-space, of a usual tworesonator klystron. The back-coupling is adjusted to cause oscillation, and the amplitude reached before the quenching voltage stops the oscillation is proportional to the amplitude of the input signal, which may be injected into the buncher or, less favourably, into the catcher resonator; energy may be radiated from either resonator, but preferably the catcher, and the device may be used as a regenerative detector of distant objects, as in Specification 639,981. The beam leaving the catcher resonator passes to a detector system such as the push-pull one described in Specification 639,982. In another form, two cathodes 5, 32, Fig. 2, fire beams in opposite directions through two buncher resonators 71, 73, and a common catcher resonator 72. The desired quenching is achieved either (1) by upsetting the phase relations of the two beams by applying a push-pull signal to the tubular electrodes 63, 64, so that they oppose each other in the catcher 72, or (2) by permanently adjusting the phase of the beam from cathode 32 to opoose that from cathode 5, and switching it in by modulating grid 58. Detection is obtained by firing a third beam from cathode 51 transversely between catcher grids 14, 15, the voltage between which deflects this beam across apertured plate 54 to give a rectified current at plate 23. Specifications 523,712, 529,771, 530,785 and 531,251 also are referred to. The Specification as open to inspection under Sect. 91 describes also an additional feed-back path through two resonators coupled by an electron beam, to maintain constant mutual conductance as in Specification 639,983. It also states that the quenching need not be complete. This subject-matter does not appear in the Specification as accepted.