| 摘要 |
558,454. Valve generating circuits. STANDARD TELEPHONES & CABLES, Ltd., and SMYTH, C. N. Feb. 20, 1940, No. 3186. [Class 40 (v)] An ultra high frequency generator having a tuned regenerative feedback comprising distributed impedances, such as Lecher wires, co-axial lines and hollow resonators, is provided with means to control the tuning by varying the dielectric constant of at least a portion of the distributed impedances while maintaining the permeability constant. The Figure shows an oscillator OSC associated with a Lecher wire system L3, L4, having extensions into a vacuum tube T in which a space charge is produced by cathode K, control grid G1 and screen grid G2. The Lecher wires are biased through resistances R so as not to draw current during any part of the cycle and vary in effective electrical length with the distribution or density of the space charge. |
