Term used in the Los Angeles County Jail to tell inmates to shut up so the Deputy can hear his police radio while walking on the row. Usually "radio" will be yelled by a shot caller in the module or a trustee. If the tier or row is too loud and the deputy gets pissed off, there is a high probability that the deputy will shut off the phones, search cells, or find other ways to cause suffering to the inmates. "Hey baker row. Radio!! Deputy walking front to back!"
Radio that shit! Daniel S.