Usually the frequencies public safety uses, they are licensed for, but they may or may not be monitorable. Those frequencies or trunked systems may not be in the database if nobody has searched and identified them in use yet. Or in rare instances, public safety may have unlicensed channels in their radios for tactical purposes which you’d only stumble upon via searching on your radio.
Don’t rule out listening to old pd or fire repeaters that have been superseded by newer systems as the old radios may still be in the cars and used for tactical or car-car. Also check public works and highway department repeaters during non-business hours as these can be used by public safety for non-dispatch conversations. Some daily unit-unit conversations take place on statewide channels like MABAS Fireground Red so listen to those too.
Some agencies encrypt their tactical communications while others choose to use cell phones for that purpose. A small minority encrypt even their dispatch operations. Also, there are a few agencies that use digital formats that are not encrypted but cannot be decoded with a digital scanner unless the scanner is hooked up to a computer running special software like
Digital Speech Decoder.
If you do find something on the radio of a sensitive nature, be wary that once everybody knows where to listen for these radio conversations, they’re soon likely to move them to a more secure system.
