Federal Signal Digital MSK
The Federal Signal Digital signalling protocol developed for Federal Signal's various warning and mass notification appliances. This signal is used for activation and telemetry of all units in a network.
The modem can be used in tandem with Federal Signal's Commander Digital System (aka SFCDware).
This protocol is commonly found among their line of mass warning and notification appliances. It is often heard over public safety/fire/police radio to control warning sirens. The entire system can be configured to transmit daily at a user-defined time to poll health checks on units in the system or manually commanded to activate or deactivate one or more nodes within a system. The protocol may also be used to remotely upgrade or program units if desired.
Specifications
- 2FSK Minimum Shift Keyed modulation
- Mark: 1200Hz
- Space: 1800Hz
- Baudrate: 1200 baud
- Error Correction: CRC16/XMODEM (poly 0x1021)
Hardware
For command and control, the Federal Signal SS2000+ encoder is typically used to interface with SFCDware and control various nodes within a system (be it Informer radios, FC controllers, or more). This device can be used standalone or attached to a PC running SFCDware for a graphical interface to a siren system. There is also a cut-down version called the Modem-MSK which will only work with a computer attached. This unit is also used in their mobile activation case (MAC-1/2)
Decoding Software
If you want to set up your own siren in SimTX you may ask @null_0xf4 in discord.