Components for a circuit board

[I_Love_My_Vans]

Hi guys + girls

I want to dive into making some hardware. I am not an electronics nerd but I fancy making (or at least attempting to / learning in the process) a basic version of a device that would usually cost upwards of £500 (A motorcycle intercom, see below for more info).

I want to know whether there are any specific sites (other than Maplins) that I should be looking at to purchase components, I have had a look at how to create my own PCB (although a breadboard will be sufficient whilst I am testing)... the main component I am after is a bluetooth chip to take the audio from my TomTom and output it to two pairs of earpieces.

Also are there any decent electronics forums that you could suggest should I have any problems?

Any way... proceed to ridicule me




More info:

The device I am trying to make will simply take audio in from a number of sources (1x bluetooth, 2x 3.5mm jack, 2x microphone) and output then to two pairs of ear pieces.

[Jenner]

Try DigiKey for packs of electronics. They have a good selection. Yes, do your development on breadboards for now.

For circuit board design, you typically draft it up in something like ExpressPCB (which is free). This allows you to design each layer and then find a manufacturing company to make them for you. I'd actually recommend a manufacturing place that will attach the electronics as well, so they ship you finished product. The investment will be a little high at first, but if you plan to market and sell these then it's probably your lowest cost solution.

When ordering printed circuit boards, the setup-fee is your biggest enemy for a small-run. Setup-fees (the cost to set the machinery up to run your product) can run about $900 US for a somewhat complex board; even if the price per board is only $50 US after that (that's a board fully loaded with it's hardware). Of course, the more you run, the cheaper it gets.

[I_Love_My_Vans]

Thanks for your advice, I don't plan on 'mass producing' them as such, and therefore would want to make / assemble the PCBs myself... also a great opportunity to learn :-)

I have seen some tutorials / videos on how to create basic single sided PCBs using ExpressPCB. I guess if I manage to create something half decent then at least I will have the plans to send off to a proper manufacturer.

Have you ever created any electronics? It would be good to hear what you (read, you all) have made.


Cheers!
Ben

[Arrow_Raider]

I use Jameco and Mouser for ordering my electronic components.
http://www.jameco.com
http://www.mouser.com

[Jenner]

I've engineered a few boards for industrial applications. I build them via a breadboard kit and when I got what I want, draw up the circuit diagrams and them design up the PCBs for the circuit in ExpressPCB. After I'm done with that, I give the CAD files and parts list to purchasing and they forward them to various PCB houses for construction. After a few weeks, some sample boards arrive; I test them and if all goes well, we order batches of 50.

[BackWoodsCoder]

I'm not sure if TigerDirect has a UK counterpart, but they're pretty handy when it comes to ordering electronic components.

[abhijit]

I'm not sure if TigerDirect has a UK counterpart, but they're pretty handy when it comes to ordering electronic components.

The UK Counterpart is http://www.misco.co.uk/

[I_Love_My_Vans]

What about a dedicated forum for this kind of topic?

[BackWoodsCoder]

The UK Counterpart is http://www.misco.co.uk/

interesting, wonder why they have different names

[dilettante]

The ideas and the parts sources mentioned are all excellent for hobbyists.

As for web sites, they typically have a narrowed focus. One I used to frequent is http://www.6502.org/ and I'm sure there are many others supporting different categories of hardware projects.

[Shaggy Hiker]

There are places that will take your PCB design and create the board cheap. If you start into making your own PCBs, be aware that you will be messing with some seriously caustic and toxic stuff. Dealing with the storage and disposal of that stuff is enough to make the prototyping costs worth it. They aren't all that high, for the most part. The figures Jenner was quoting appear to be fully built boards...or some such. I was looking at one prototyping site and the cost was really cheap (though I don't remember how much), whereas I would not consider the price that Jenner quoted as being cheap.

[Jenner]

Yea, my pricing is for a fully assembled board, and probably more in tune with a large manufacturing operation. I'm sure you can do better if you look.

[I_Love_My_Vans]

Excellent, thanks for the info so far... it's been great!

I'm still trying to figure out whether it's feasible / possible to slap a bluetooth chip to enable communication between my TomTom, anyone had any experience of this? A google search hasn't returned many results for this particular problem.


Cheers!

[Arrow_Raider]

Do you know how the TomTom sends audio through bluetooth? If it just does serial (RS232) over bluetooth, that would be the easiest to work with, but it probably doesn't do that... The first thing you need to figure out is what it does do, and then we can figure out where to go from there.

Are you able to connect the TomTom to a computer that has bluetooth?

You're going to need to hook up a bluetooth module to a microcontroller and then you'll need to program the microcontroller to be able to control the bluetooth module. This is going to be the hardest part, and it is dependent on how the TomTom works with bluetooth.

[kleinma]

You could start with something like this:
http://www.thinkgeek.com/gadgets/electronic/b80b/

[abhijit]

Start here --> http://www.starcom1.com/price_list.htm

[Shaggy Hiker]

Take a look at SparkFun, I got some bluetooth chips from there that work really well. You give it 5V, ground, and low voltage (logic level, not RS232 level) Tx and Rx, and it works quite nicely. Seems that I paid under $100, though it was a couple years back, and I don't remember.

[I_Love_My_Vans]

Do you know how the TomTom sends audio through bluetooth?

No, unfortunately I do not but I will have a poke around the internet to try and find out how it does.

Are you able to connect the TomTom to a computer that has bluetooth?

Yes, when I am able to discover the TomTom and connect to it on my Windows XP machine, it appears as an audio device.

@abhijit problem with bike intercoms is that unless you're prepared to a lot of money they are usually very poor quality, especially with regard to the head set.