| 摘要 |
1,045,543. Keying carrier frequencies; transistor switching circuits. SIEMENS SHUCKERTWERKE A.G. Jan. 15, 1964 [Jan. 30, 1963], No. 1872/64. Headings H3R and H3T. A transistor oscillator tank circuit C 3 , n 1 , has a coupled feedback winding n 2 connected through equal resistors R 3 , R F to a common potential (A), the centre tap of the feedback winding being connected to the transistor base so that when R F is increased by a magnetic field applied thereto, feedback is initiated to start oscillations. The oscillator output taken from a further coupled coil n 3 is rectified at D 1 , D 2 to produce a D.C. switching control. from a further coupled coil n 3 is rectified at D 1 , D 2 to produce a D.C. switching control. The resistor R F may be varied by an electromagnet. |
