What is the purpose of MU-4 User IDs?
User IDs are used to prevent interference to third party systems that also use MU-4 within the same area. It is unlikely but not impossible for 2 or more system manufacturers in the same area to end up using same user ID.
To avoid this, Circuit Design recommends users to obtain a unique user ID when implementing the MU-4 into their system. To obtain a user ID, please contact Circuit Design.