To connect the receiver and transmitter, various technical components must be compatible: The operating frequency, the modulation type, the clock rate at which the data word is sent, and the coding method. The coding method is the "encryption" of the radio signal. When programming the 1st hand-held transmitter, you must choose either linear or KeeLoq code, as they are not compatible with each other.

The same coding is sent with each transmit command. The handheld transmitters are predominantly equipped with a coding switch to set a personal and individual coding. This ensures that no neighboring systems are controlled unintentionally. Since the coding is used again unchanged with each transmission command, these radio systems are less secure against eavesdropping and imitators.

• Systems with several/many handheld transmitters where the security requirements (underground garages, warehouses, parking lots, lighting systems, etc.) are rather low or can be improved in other ways, e.g. by an alarm system/video surveillance.
• When using hand-held transmitters with coding switches, a teach-in operation is only required once on the receiver (for each transmitter button that should have an effect).
  Any number of handheld transmitters (same coding setting) can operate on this receiver (the memory space is virtually unlimited).
• In the case of subsequent delivery of handheld transmitters with coding switch (spare part, system extension, etc.), the customer can set the coding himself and put the handheld transmitter into operation; it is not necessary to get to the receiver.
• The offered choice of transmitters (micro handheld to multi-command industrial and forklift transmitters) is the largest here.

Also referred to as change code, roll code, rolling code, SomLoq, etc.
The coding changes with each actuation of a handheld transmitter key according to a highly complex algorithm. A code that has been sent once is only repeated after billions of actuations.
The radio system is therefore very secure against eavesdropping and misuse.

• Systems with few handheld transmitters, but with increased security requirements (private systems, banks, sensitive areas, etc.)
• One teach-in operation on the receiver is required for each handheld transmitter button!
• The number of teachable handheld transmitter keys on a receiver is limited (the memory capacity depends on the receiver type).
• When hand-held transmitters are delivered subsequently (spare part, system extension, etc.), the receiver must be relearned. The customer is usually not in a position to do this. A service call becomes necessary.