Step 1 - Press SETUP
Step 2 - Enter the following number 29163
Step 3 - Press 1 System
Step 4 - Press F2 (DN) multiple times, all the way to the bottom of the menu until it won’t scroll any further.
Step 5 - Select the System ID option. (The number or position on the screen varies depending on transmitter firmware version.)
The System ID will appear flashing on the screen. To change it, type in the new number and press Enter.
When done, press the F4 to exit out.
NOTE: Station ID will appear as you are scrolling down but this is for a different purpose. Please continue scrolling until you find System ID.