CAUTION
If you have never performed an upgraded on a DD, SD, HD, or XtenDD switcher read through the following instructions. The thumbwheel dip switch settings vary slightly but the process is the same. If you have any hesitation, or are not comfortable after reading these notes, you should hire our on-site Field Service Engineers to perform the upgrade. You can also call Customer Service at 1-800-547-8949, option 2 for help.