First attempt at demodulating MOTOTRBO digital radio transmissions from a newly-installed local public safety system. Signal received with a Uniden Bearcat BC144XL scanner, I tapped the baseband audio from the FM discriminator IC and fed it into the sound card of a linux PC running Digital Speech Decoder (DSD) 1.4.1 under Debian Wheezy. Currently this is the only known method to externally capture audio from this type of system. NOTE: this is merely a form of digital modulation, the transmissions were NOT encrypted for security by the operator.

b5bartender