The invention relates to contactless electronic switching devices in which a screening electrode protects a response electrode from undesired influences and at the same time does not impair the sensitivity of the switching device. The contactless electronic switching device includes an oscillator 10 susceptible to external influence, an electronic switch controllable by the oscillator and in which the oscillator features an amplifier transistor 15 and a resistive-capacitative feedback circuit 16, a response electrode 17 connected as part of the oscillator, an alteration of capacity between response electrode and earth 18 causing the oscillator 10 to commence or cease to oscillate, and at least one screening electrode 19 surrounding the response electrode 17, the transient alteration of potential difference between response electrode and screening electrode being approximately zero. This is achieved by coupling the electrode 17 to the emitter of amplifier 15 directly or via emitter follower 24. IMAGE
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