I know nothing - HELP!

Discussion in 'The Projects Forum' started by Meh, Jan 22, 2012.

  1. Meh

    Thread Starter New Member

    Jan 22, 2012
    Seriously, I'm brand new to this stuff and have never taken a class or anything. In fact, I just found out what a breadboard/protoboard was the other day and ordered one on ebay. So again, I know nothing about this stuff but I'm anxious to learn.

    I want to make a circuit that can be set to light an LED and set off a buzzer at repeated intervals every 12 hours. I would also like to have the LED and buzzer turned off with the push of a button but to have it go off again 12 hours later. I want all of this to be on a very small scale (about the size of a quarter).

    As mentioned, I bought a breadboard and have also purchased some 555 timers, 4020 ripple-carry binary counters, a 6 mm mini push button on/off, a 30 mm x 15 mm 8-ohm speaker, jumper wires, and a pack of small 1 volt watch batteries. I bought this stuff just by using logical reasoning in thinking about the circuit but again, I have no idea if this is at all what I need as I've never done anything like this at all.

    So the question: What else will I need? How do I build this? If I'm in over my head (and I feel like I am), where can I go to get someone to build this for me for a small fee? How much would it cost to have someone more experienced do something like this?

    HELP please!
  2. MrChips


    Oct 2, 2009
    Your best bet will be to learn to program a microcontroller unit (MCU).
    Someone on this forum would be willing to do this for free or at least trade for something else such as extra components.
  3. Meh

    Thread Starter New Member

    Jan 22, 2012
    Thanks for the response. What exactly is an MCU and why would it be a better choice? I'm not questioning you at all, I would just like to learn more about all of this.

    Also, if anyone is interested in helping me out with an MCU or whatever other methods they think would work, please let me know.
  4. tracecom

    AAC Fanatic!

    Apr 16, 2010
    An MCU is a microcontroller unit, i.e., a computer on a chip. They are available in several flavors, e.g., PIC, PICAXE, Arduino, Basic Stamp, etc. They can be programmed to do quite a lot of different things like timers, LED flashers, sound makers, as well as read a variety of sensors and clocks.

    That is not to say that what you want cannot be done with separate components, maybe even with some of the ones you have. However, without using SMD (surface mount devices), the assembly will be bigger than a quarter.
  5. Meh

    Thread Starter New Member

    Jan 22, 2012
    Great, thanks! I'll keep this thread here and bump it from time to time until someone offers to help me out (i.e. do it for me because I have not a clue). I'll post a similar thread in some of the other categories.

    Thanks again guys! And if you're interested in helping in exchange for some components/payment, let me know.
  6. PaulEE


    Dec 23, 2011
    If you want to get into electronics, I would suggest you give it a go for yourself...if you look up "pickit2", you will see an affordable kit that has both the programmer, software, and prototyping board.

    Everyone fluent in PIC C/assembly will be more than happy to help you get this done. It's not too complicated, but there are a few subtle things that'll need to be worked through.

    If I had to write the pseudocode (topological outline of what the code does as opposed to what it is):

    PIC powers up, *PIC begins counting, PIC determines that 12 hours has passed and signals lights/alarm/whatever, PIC stops and waits for the user to hit "reset" button, PIC repeats*

    Are you in the USA?
  7. shortbus

    AAC Fanatic!

    Sep 30, 2009
  8. wayneh


    Sep 9, 2010
    Not sure what you mean by "small" fee, but I doubt you'll find anyone to do this for a fee you'll be happy with. Someone may take it as a charitable project, pro bono, but good luck with that.

    I don't know how you could keep it that small, but you might consider a hack solution. By that I mean finding a commercial timer you like and hacking in a light, alarm and switch that meet your specific needs.
  9. Brownout

    Well-Known Member

    Jan 10, 2012
    What exactly to do want this for? The reason I ask is becuase I might be able to find a kit or schematic for what you want.
  10. Bernard

    AAC Fanatic!

    Aug 7, 2008
    How long is the LED suposed to stay on every 12 hrs.? How much of the ckt goes into the quarter, speaker, batteries, & timer? How thick is the stack of quarters? Use one 555 as clock for 4020 counting to 12 hours, trip another 555 for alarm duration, 3rd 555 as oscillator to drive speaker. switch to reset everything. What part of the world are you in- just in case of shipping?
    Last edited: Jan 24, 2012
  11. Wendy


    Mar 24, 2008
    Don't forget, the OP wants this under the size of a quarter. A µC SMT style could do it, but not much else will.
    PaulEE likes this.