Full-Feature Audio-Processing, Signalling and GPS Data for
Half Duplex FRS, MURS, PMR446 and GMRS ‘Leisure’ Radios
Features
• Automatic signal type scanning and IRQ on detection of valid Rx signals, level or RSSI
• Voice processing facilities, including Tx and Rx gain setting and voice/subaudio filtering
• Tone generator for caller recognition tunes • C-BUS serial host interface
• Programmable power down control • RF interface allowing 1 or 2 point modulation
• Programmable signal detection thresholds • Programmable soft limiter
• Low Power operation with Zero Power mode • Enhanced CTCSS and 23/24 bit DCS codecs
• Uncommitted Aux ADC with switchable input to monitor signals
• Zero ‘talk down’ CTCSS decoder performance prevents dropouts
• Silent operation by removal of unwanted calls • ‘All call code’ and ‘monitor’ modes for CTCSS
• Selectable voice companding • Audio scrambling
• XTCSS channel and data signalling
• Robust Half Duplex FFSK/MSK modem, 1200/2400 bps, gets data through when signal is too degraded for voice – for text messaging/paging, location transfer, etc.
Applications :
• Robust automatic packet data protocol with: Error correction and detection, Interleaving and
