Chuck, Looking at magic black box stuff. I will not even try to explain what is going on inside the 555 right now. They will just learn how to use the 555. Not even going to go into depth on the caps and resistors.
This is a small part of a larger project. We are just trying to add some bells and whistles to their presentation to make it stand out a bit. -- Best regards, Mark mailto:m...@mailmt.com Myakka Technologies, Inc. www.MyakkaTech.com Proud Sponsor of the Myakka City Relay For Life http://www.RelayForLife.org/MyakkaCityFL Please Donate at http://main.acsevents.org/site/TR/RelayForLife/RFLFY12FL?team_id=1030009&pg=team&fr_id=37555 ------ Friday, January 9, 2015, 12:12:04 PM, you wrote: CM> In my mind, a 555 timer is more difficult to understand as it has a CM> comparator and flip flop inside amongst more things. CM> I guess it depends on the opinion of what is easier to understand. In my CM> mind, relays are easier to understand than logic in chips like that. CM> For example, you can have a push button discharge a cap. That cap would be CM> across the windings of a relay. Big cap fed via a resistor. Push the CM> button and the relay opens until the cap charges back up. CM> That is a pretty simple timer circuit. t=RC. CM> If you want to cut down the size of the big cap and obvious short life of CM> the pushbutton, you can go one step further and put a transistor in the CM> circuit etc etc. In my mind that is much simpler and easier to understand CM> than a 555. CM> However, if you are looking for a simple block diagram understanding, the CM> 555 is the way to go. CM> I realize that I may not have the ability to look at these things as a kid CM> would look at them. What is simple to me may not be simple to them and vice CM> versa. CM> -----Original Message----- CM> From: Mark - Myakka Technologies CM> Sent: Friday, January 09, 2015 10:04 AM CM> To: Chuck McCown CM> Subject: Re: [AFMUG] OT - EE help please CM> Chuck, CM> I'll be working with the kids again tonight. Hopefully we'll have CM> time to go in a bit more detail. The 555 is appealing being it can CM> do many things. We can use it as a timer, we can use it to flash CM> leds, etc. The kids will only have to learn about the 555, caps and CM> resistors. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com
