In this guide you will find a description and diagram of radio COM-port. The device is simple it can collect any who knows how to handle a soldering iron. All design details are available and affordable. 2, the device works fine. The use of this device is very wide. In the archives this guide as a gift is one more leadership "system connection between the two computers laser pointers at a rate of 115200 at a distance of about 300 meters, resistant to all sorts of illumination of the available components is simple to manufacture, the distance can be increased.". So you buy 2 guidelines for the price of one.