Improvements in or relating to negative feed-back transistor amplifiers

摘要

765,998. Transistor amplifying circuits. PHILIPS ELECTRICAL INDUSTRIES, Ltd. March 25, 1955 [March 26, 1954], No. 8778/55. Class 40(6) In a negative feed-back amplifier having transistors 4, 5 and employing an input transformer 6, feed-back from resistor 11 is applied over a tertiary winding through resistor 12 in order to reduce the size of the transformer. A microphone 1 feeds over a matching transformer 2 a pre-amplifier transistor 3, feed-back being taken to a tertiary winding on the transformer 2. The working-point of transistor 3 is stabilized by resistors 8, 10 decoupled by capacitor 9.