Audio activated switch- components problems.

Hi

I would like to build this circuit, but as I live in Iceland I cant seem to find neither the
comparator nor the mosfet. I´ve found them in online stores but with shipping charge the cost is up to about 50 dollars for those 2 components. I was wondering if anyone could recomend replacement components that would work equally well, the only thing I would rather not want to change is the power source I was hoping to be able to use a 1/3n lithium cell.

Any help would be greatly apriceated.

here´s a link to the circuit

http://www.discovercircuits.com/DJ-Circuits/audiodetect1.htm

Ahh, Alas the battery is what makes them hard to find. Easy to find (and cheap) fets like the 2N7000 would like 3 volts worst case to turn on. The comparitor needs to be low power but also needs to run at low voltage which rules out a lot of easy to find ones. If you want to take a chance on a design that won't quite worst case you could try LM193, 293, 393 and the 2N7002. This combo you might find. I would probably work and battery life would be about 300 hours or so. Short of that all you can do is go to a site like mouser and write down a bunch and see if you can find them locally.

Thank you so much for the advice, I will check with the supplier and hopefully will get this project in motion soon.

I´ll put an update on the project when it´s done.

cheers.

Let me know if you can't find anything. I could probably regular mail them to you for a couple of bucks.

Will do, thank you for that. One more question if could help. This circuit is for a collor for my dog, and I am going to attach a vibrator to it, so that when she barks it will vibrate, do you know in sted of which resistor I can put a potention meter to ajust the vibrating level?

The 150K sets the amplitude of the bark that will turn it on. (smaller is more sensitive)
The 4.7 meg. and the .1 ufd. cap. by the fet determines how long it will stay on (right now about a half second) If you want this longer you might want to change the .1 cap to a larger one instead of going much larger on the 4.7 Meg.
If it is one of those little motors from like from a cell phone you would want to add a diode across the motor (cathode to +3volt side. The circuit cannot drive a lot of current. How big is the vibrator?

the next on my to do list was to open some old cellphones and check my option, but when you say that I should add a diode across the motor and connect the cathode to the 3volt side, where do I then connect the Anode? I want the vibrator to be as small as possible because I have a chiuahuah, I wanted to get all the parts I can in smd and make as compact as possible. Any and all advices will be greatly apriciated.

thanks again for all the help