Electronic tuning circuit for radio receiver - has tuning voltage stabilised by Zener diode in series with resistor

摘要

The receiver electronic tuning circuit superimposes a control voltage on the tuning voltage. The tuning voltage is stabilised by a zener diode and resistor in series. - The collector/emitter path of a transistor (6) is connected in series with this stabilising circuit (2, 4) on the zener diode side. The transistor base receives the control voltage e.g. from a discriminator. The transistor base may be connected to the tapping of a voltage divider connected across its collector/emitter path. The supply voltage for the stabilising circuit is obtained from a second zener diode (10).