A code plug is the program written to a radio using the CPS which contains radio settings and data for each repeater (frequencies, colour code, talk groups….)
CPS (Customer Programming Software)
This is the manufacturer (and sometime radio) specific program that is used to create a code plug. It’s free from the majority of manufacturers.
DMR (Digital Mobile radio)
A generic term used to describe the digital version of standard analogue transmissions. Contrary to popular belief, it is not owned by Motorola, but is an open standard of digital transmission.
In simple terms – 2 repeaters in one box. Each slot uses 6.25kHz of the 12.5kHz bandwidth and thus has twice the capacity than that of an analogue repeater.
These could be seen as channels directing your QSO through a “telephone exchange” known as a c-Bridge based on which talk group you chose.