Since the Body Detector is intended to detect any and all body presence, an On/Off switch that is mounted close to the circuit could in some instances present a problem. At the same time, to include any delays in triggering might be self-defeating, since some applications will require instant triggering such as a "turnstile counter" or an anti-tamper alarm.
A key switch was thought to be the most obvious solution for switching off and may be located some distance from the circuit. This may be inserted in place of (in series with) S1a. Best of all, any delays in triggering should be included in the external circuit. The author mounted the on/off switch on the case for the purpose of neatness and easy setting up. In most applications, this did not cause the circuit to trigger when switching off.
However, solder pins have provided for compensation capacitors (Cx) at poitions E8 and E9 on the oscillator board. Their insertion may be left until the circuit is complete and is found to be working satisfactorily.
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