I just went through this with a few b tech 50x1s so each of the freqs 1-30 are hard coded to the radio and cant be changed.... 1-7 ar the frs/gmrs and low power, you can change the name and the tone but the freq and power will always revert back to the factory set. 8-14 and set for frs 8-14 and are RX ONLY 15-30 are able to go to the High power TX, 23-30 are the repeater input spots, so if you need to program a repeater freq or a 550 repeater then it HAS to go on the slot 23 and 575 on 24 ect thus you are not able to program multiples of the same freq but different slots... 31-256 are RX only IF you try to add, say 462.550 it will work as expected if put into slot 15, but if you try to put 462.550 into slot 16 everything appears to be ok, until you write to the radio, slot 16 will change back to 462.575 even though the name you added and tone are saved.
the same is true for the repeater channels, they can only be in the 23-30 slots on chirp, 23 being 15 in etc
