MortiRemoteSafe components you'll need to buy

You'll need to buy the following bits:

Component	What does it do	Source	Price
Digital safe	Holds your keys	Can buy these from lots of places, eg hardware store, or online, eg http://www.ebay.co.uk/itm/140598411041 or http://www.ebay.com/itm/370612338693	Around £25
Microcontroller	This plugs into your PC and decides when the safe should be open or closed	http://www.modtraders.co.uk/minimus-avr-usb-development-board.html	£7.90 including UK postage
Remote control unit	This has two parts, one goes outside the safe and one inside. The outside part connects to the microcontroller board and the inside connects to the safe controls.	http://www.ebay.co.uk/itm/330688018378	£8.99
Power supply	This powers the remote control receiver inside the safe. Any mains powered power adaptor will do, as long as it is between 6v and 12v and as long as you don't need it for anything else (you'll need to cut the connector off the end)	You probably have one hanging around from an appliance you no longer use, otherwise cheapest way from ebay appears to be buying a USB hub, such as http://www.ebay.co.uk/itm/250992988193	£4
Single core wire	For connecting between microcontroller and remote transmitter. Only need less than a meter	Lots on ebay, such as http://www.ebay.co.uk/itm/330733924368	£2
Terminal connector	For connecting wires together	http://www.ebay.co.uk/itm/300463364739	£1.50
Optional - Polymorph plastic sealant	For covering the electronics if you think creative fingers may try to take your unit apart and short out contacts to cheat	http://www.ebay.co.uk/itm/170762527811	£6

For some of the above bits, check out local hardware stores or pound stores for cheap alternatives. The total of the above is about £56 including optional bits and if you can't find anything cheaper, and about £40 if you have lots of standard bits already.

Alternative sources:

• Just about any digital safe will do, with the following conditions:
  • Must be battery powered
  • Must have small holes at the back (usually for screwing to wall) for running a cable through
  • Must have a screw panel on the back of the door which gives access to the controls inside
• The microcontroller must be the one specified above (Minimus) for the firmware I've developed to work. There are a lot of similar boards such as Arduino; the firmware could probably be converted to work on any Atmel based board. Contact me for more info. But the above Minimus is by far the easiest and as far as I've seen the cheapest
• The remote control device is a remote 'key fob' which controls a relay. If you have another similar board in mind, it's necessary that you can take the key fob apart and pull the switch off to get to the appropriate electrical contact, and that the receiver end has a relay and the power supplies are right (5v for transmitter, whatever the power adaptor voltage is for receiver)
• If you want to reduce cost, the above remote control is 4 channel but you only need 1 channel, so you can buy a 1 channel device - http://www.ebay.co.uk/itm/230747393758 - which is £3 cheaper. I suggest the 4 channel just in case you have a problem pulling the switch apart on one of the channels, you can have another 3 goes at it.

Plus you'll need a few other bits:

• Insulating tape
• A nut or washer (to prevent a wire slipping through a hole)
• Small piece of rubber mat or wad of paper (to insulate the back of a board)

Tools you'll need:

• Small screwdrivers (flat and crosshead)
• Something to strip insulation off wire
• Thin nose pliers
• Preferably a soldering iron with solder (not much needs soldering) but you could make do without one