Article 9362 of comp.robotics.misc: Path: news.scruz.net!noos.hooked.net!www.nntp.primenet.com!nntp.primenet.com!enews.sgi.com!news.mathworks.com!newsfeed.internetmci.com!in2.uu.net!viper.shadow.net!usenet From: jdunfee@shadow.net (Joe Dunfee) Newsgroups: comp.robotics.misc Subject: 555 Schematic for Servo Control Date: Tue, 17 Sep 1996 03:50:33 GMT Organization: Shadow Information Services Lines: 44 Message-ID: <51kj5d$73e@viper.shadow.net> NNTP-Posting-Host: ppp-mia-90.shadow.net X-Newsreader: Forte Free Agent 1.0.82 In my school electronics book there is a schematic for generating the pulses necessary for controling a standard R-C servo motor. But unfortunately it doesn't specify the voltage. I know I successfully built a servo controler with a 555 , but don't recall the specifics, nor what schematic I used for it. It definitely didn't run the 555 at 90% duty circuit and invert the output. I used the output from pin 3 directly. It worked great. Here is the schematic... _____ +5 Volts | | | V | | ___/\/\/\_|___/\/\/\_________| | 5k Pot 4.3k | | | __|____|__ | | 4 8 | |____________________|7 | | | | | | 555 | | 1N457 Diode | TIMER | |____|\|_____________|6 |___________ | |/| | | | Output to | | | | Servo | | | | |__/\/\/\______|_____|2 | 56k | |__1____5__| | | | _|_ | _|_ 0.33mF ___ | ___ 0.1mF | | | |________|____| | --|-- -|- - The formulas for the 555 timer and the programs I have found that automate some of the variables all disallow a duty cycle under 50%. So I am somewhat stimied on how to proceed. Actually I am now wanting to use products like the basic stamp. (although parallax has delayed shipping almost a week, but didn't bother to let me know - I think I may go with Scott Edwards Electronics instead) But I would still like to finalize a design to use a 555 to control a servo from a Pot. Anyone else have any input on this?