Electronics noob wants to create a wearable RF detecting haptic sensor

[Marley577]

So my idea is to take an rf sensor that is able to detect signal strength in the 2.4Ghz range (spectrum of wifi and most wireless devices or so I have read), and connect it to any sort of motor or vibrator that I could wear in contact with my skin and would increase in vibrational strength in correlation to the signal strength, thus allowing me to feel 2.4Ghz signals (6th sense?). The entire apparatus should be fairly small and wearable as a bracelet or arm band thing. I am very much a total beginner at this and thought that if, eventually, by the time I piece this whole thing together, I would have taught myself the basic electronics I desire to learn. So where should I begin? What do I need to know? I found this, I have no idea if it will do what I need done or not:

http://www.qsl.net/n9zia/wireless/pics/LED_sig_meter.png
Is this a step in the right direction? Or am I already headed off the deep end?

I signed up here and hopefully you all can help me out! Thanks!

[mstacho]

hahaha that's a fantastic little project.  It seems like it'll be fun, too, but if you're an electronics newbie I might suggest that you go for a much simpler project.  This isn't because I don't think you can put the circuit together, but I just don't think a newbie would understand why they are putting all the sensors, capacitors, etc into the circuit in the first place.  For instance, can you explain why there is a 0.1uF capacitor going into some of the pins of the RF detector chip?  Does it matter if it's 0.1uF or 0.2?

My point is that finding a circuit online and just putting it together will give you experience assembling the circuit, but you'll still be stuck when you have another project that you'll need to do the design for but won't understand how.

How about this: put that idea on the backburner and return to it once you're more familiar with electronics ( throughout this entire post, I've assumed you have very little familiarity, so if anything I'm saying is wrong, just ignore me :-P )

Make a simpler project first.  Electronic dice might be fun, but I'd suggest something that will help you to make this eventual project work.  What about this:  see that LED circuit there?  Why not make it and attach it to a potentiometer, and see if you can get it to light up the LEDs like you'd expect it to.  This would mean you'd get to learn HOW the LM3914 chip works and, by extension, how to read/find datasheets for the given chips.  Once you do this, then you can PROBABLY move into the full circuit (without any vibration yet, just replicate what's already been done), since by that point you'll understand a bit more about what's going on.

Once that's done, it's time to learn which of the outputs of the AD8313 produces the intensity, and then how to wire that into a motor (I'll give you a hint: it's probably not a good idea to just dump the voltage into a motor!  You'll need to design a way to turn that voltage into a useful motor signal...I'm totally not going to tell you how to do it yet   You'll have to try on your own)

Of course, if you DO jump right into that circuit, it'll be a pretty big challenge but will still be valuable experience.

**EDIT: Oh, and that part about all components being SMT is not good for a beginner.  You want "DIP".  "SMT" is Surface Mount Technology, and it's the SUPER small little chips that they use a machine (or a REALLY good hand solderer) to put onto boards.  "DIP" is "Dual Inline Pin", and it's the more familiar "computer chip" that you'll be able to find.  It's much easier to solder/work with DIP than it is to do with SMT unless you happen to want to get it printed by a professional company.

MIKE

[Soeren]

Hi,

So my idea is to take an rf sensor that is able to detect signal strength in the 2.4Ghz range

At what distance do you expect to detect how large(/or small) an RF power?

[Marley577]

How about this: put that idea on the backburner and return to it once you're more familiar with electronics ( throughout this entire post, I've assumed you have very little familiarity, so if anything I'm saying is wrong, just ignore me :-P )

Make a simpler project first.  Electronic dice might be fun, but I'd suggest something that will help you to make this eventual project work.  What about this:  see that LED circuit there?  Why not make it and attach it to a potentiometer, and see if you can get it to light up the LEDs like you'd expect it to.  This would mean you'd get to learn HOW the LM3914 chip works and, by extension, how to read/find datasheets for the given chips.  Once you do this, then you can PROBABLY move into the full circuit (without any vibration yet, just replicate what's already been done), since by that point you'll understand a bit more about what's going on.


MIKE

Haha no you are completely correct there. Thank you very much for this response I think I'm going to do exactly what you told me to do. I like the idea of electronic dice because I can just find a tutorial that can set me up and get me geared for the next project (like finding out where in my garage my solder gun is?) I'll check back in here if I need any help or discover anything exciting, although I guess the best way to figure this out is probably by trial and error and a hard sweat over an electronics manual.

[mstacho]

Good luck! And don't be afraid to ask questions.  sometimes, someone on the forum had exactly the same problem you did and just knows the answer.  I've probably learned more on this forum about electronics than I ever did in any of the classes I took.  You are right, though -- one doesn't learn electronics by reading.  Learn by doing...and asking and then doing more :-P

MIKE

[corrado33]

Good luck! And don't be afraid to ask questions.  sometimes, someone on the forum had exactly the same problem you did and just knows the answer.  I've probably learned more on this forum about electronics than I ever did in any of the classes I took.  You are right, though -- one doesn't learn electronics by reading.  Learn by doing...and asking and then doing more :-P

MIKE

Well, you learn electronics theory by reading.  You learn WHY the electronics work, not just what they do.  You learn what all those little values mean on the NPN transistor datasheet mean.  

Well, you could read a book or just listen to Soeren and waltr.   (And everyone else on this site who contribute to electronic related things)

Yes, and to contribute to this thread, you should start with something easy.