Following the war of Everon the island was inundated with surplus military equipment. Seeing an opportunity to make some money back the government started selling items such as radios to the people of the island for those who wants to communicate with each other.
General information
The AN/PRC - 68 radio can be bought from general stores in each main town market costing around $2000.
Each radio has two transponders that can be set to different frequencies ranging from 32MHz to 96MHz. If two radios are set to the same frequency, they can communicate with each other.
Encryption
Encryption chips are available to purchase from smugglers village once it is captured. These chips give you the ability to encrypt your radio meaning only people with the same code will be able to talk to each other if they are using the same frequency.
Once a chip is bought you need to inspect the radio to change the encryption, if the encryption needs to be changed at all a new chip will need to be bought.