Electronic tranceiver + powersupply

Hi,
For a schoolassignment we have to make a fictive product and we’ve chosen an electronic bike lock.
It should work the same way as an electronic car lock, with a key where you can push a button to open your lock etc. The following link can give you a clue of how the product should look like: (traiteurmiekeivan.be/jens/mc … tsslot.avi)

But now we have a problem, none of us has a technical background so we don’t know what receiver we should use to open or close the bike lock. I allready searched the net for some products and I thought the ‘K8057’ would be a good solution. Does anyone know if this would be a good choice? (velleman.be/be/en/product/view/?id=352724 )

But that wasn’t are only problem. If we would use that receiver we will have major issues with the batteries. We figured out that if we use 6 AA batteries our lock works for 16 hours (I guess we did the calculation wrong) so we’re looking for a way that the batteries work longer.

So we started thinking of what electronic toy also has to receive constantly, and we thought of a keyfinder (a thing makes noise if you whistle, so you can find your keys back).

So now is my question: does anyone know how such a keyfinder works (especially how the batteries work, when does it receive …).
And if anyone knows a solution for our problem it’s also welcome.

Thank u

hi, this thing is not my strongest point, but as a suggestion you could
a) use revhargeable batteries
b) buy one of these keyfinders and take the workings out- try to find out the circuit that recieves the signal and the one that makes the sound. Then I would use a multimeter to find out what goes on and then link the reciever to a relay or motor/solenoid.

You man need an extra battery for the workings (motor or whatever you use). I saw the video and it looks good… Just keep going at it and eventually you will find something that works! :slight_smile: