| 摘要 |
<p>ELECTRONIC SIREN An electronic siren wherein push-pull output transistor stages are used to drive an inductive load for producing an audible signal. Thermally induced base leakage currents are diverted from the transistor stages through the use of a control network which alternately removes a constantly asserted forward biasing signal therefrom. A current diverting network operating in conjunction with a series connected common emitter resistor serves to limit excess current flow at the output transistor stages and a shutdown network responding to a non-saturated on condition at either transistor stage serves to shut the circuit down in the event of short circuits and the like.</p> |
