摘要 |
1,000,296. Thermionic valves. MULLARD Ltd. Aug. 3, 1961, No. 28241/61. Heading H1D. [Also in Division H3] A self-oscillating frequency changer utilizes a mixer valve having a planar cathode 2 surrounded by a control grid 1 and a screen grid 3 and having two independent anodes 4, 5 each co-operating with a respective side of the cathode, one anode being included in the oscillator circuit and the other being connected to an IF circuit. The valve may have in addition a screen 5 and the grids may be of " frame grid " form. |