Path: utzoo!attcan!uunet!husc6!rutgers!cmcl2!rocky8!cucard!ccnysci!sukenick From: sukenick@ccnysci.UUCP (George Sukenick) Newsgroups: sci.electronics Subject: Re: Build a "simple" timing device. Message-ID: <876@ccnysci.UUCP> Date: 9 Sep 88 15:11:17 GMT References: <2283@m2-net.UUCP> Reply-To: sukenick@ccnysci.UUCP (George Sukenick) Organization: City College of New York Lines: 16 Re: using a 555 timer as a one shot timing device: One thing to consider when using 555's : some varieties, in some "one shot" configurations, when triggered, will turn the output on for a time as defined by the RC combo regardless of the duty cycle of the trigger (ie: the output of the 555 will go high for the prescribed time); others will ADD the on time of the trigger to the time of the RC (ie: the output of the 555 will go high when activated and the RC timing will not go into effect until the trigger signal goes off). This extra time can be significant when connecting to mechanical switchs.