• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Reminder project

Is this a worthwhile Project

  • yes but likely very expensive

    Votes: 0 0.0%
  • yes and should be relatively cheap

    Votes: 0 0.0%
  • No because the idea is dumb

    Votes: 0 0.0%
  • No because the idea is useless

    Votes: 0 0.0%

  • Total voters
  • Poll closed .
Not open for further replies.


New Member
What I am looking for is a way to quickly remind me when I am leaving something behind.

What I had in mind was two items that when separated after a certain distance, one would emit a sound or buzz.

The smaller the better. At least one of the two items would need to be very small. The bigger of the two should be about Credit card sized and no thicker then a pen, preferably smaller.

Any suggestions or ideas?

Thank you in advance


I just want to say this. I few weeks ago, I suffered a stroke. What saved my life was that I had my cell phone with me and was able to call for help. Since then, I don't like to be seperated from my cell. I would without a doubt, like to have something that would warn me if I were about to walk away from it. For that reason, I think thise is a very worth while idea.


I would advise you to strengthen your own memory. For me, I just like to have nothing but myself. I don't like having all these devices in my pockets or anything. It really is quite fascinating what you can do if you strengthen your memory! I have been trying to do so each day, and I find that I can do more complex math calculations mentally, because I can remember what I have when I undergo each process. Also, you can visualize things much better because you remember more details. Nikola Tesla had superb memory and sometimes he couldn't tell which object was real; the one he was seeing in his mind or the one on the table. For many of his inventions he would place each individual part to construct an invention all in his mind! Then he would write it on paper.


New Member
two items that when separated after a certain distance, one would emit a sound or buzz.
Doesn't a young kid do that when mama leaves line-of-sight view? :)

Get an FM radio, and tune it into the blank sund of one of those get on eBay FM radio transmitters for connecting ipod to car radio. When they are separated, the radio hisses. Job done!


New Member
Attach an electromagnetic signal transmitter on the item you don't want to forget. The receiver would be bigger and you could keep it in your pocket or attached to your belt loop. When the strength of the signal drops below a certain level (due to distance from the transmitter) the receiver emits an alarm. Kind of like a smoke detector, but you use the strength of the transmitted signal as a trigger instead.

Are you thinking about making this yourself? It might be better to buy the transmitter, I don't think it would be easy to make it really small.
Not open for further replies.

Latest threads

EE World Online Articles