When programming a show with Pc•MACs, it is often necessary to run a cable from your PC to the controller you are programming. The Bt-USBTx and Bt-Rs232Rx form a ‘wireless’ cable that you can use while programming, without having to run an actual cable. Both the Bt-USBTx and Bt-Rs232Rx feature Class 1 Bluetooth transceivers. Line of sight range is approximately 100 meters when using a Class 1 Bluetooth link. This is about the same range as a WiFi link. Most Bluetooth transmitters that are built into laptop and desktop PCs will be either Class 2 or Class 3. The Class 2 and Class 3 Bluetooth links are rated for 10 meters and 1 meter, respectively. They are meant to be used with mice and keyboards, where long range is not needed. The Bt-Rs232Rx will work with a PC's built in Bluetooth, but don't expect to get full range performance.