New Open Source Data Mode FSQ

Con Wassilieff ZL2AFP has developed a new fast simple chat data mode for use on HF and VHF 

FSQ is a Fast Simple QSO mode for MF/HF. It works well under NVIS and sunrise/sunset conditions on the lower bands, and also works well for short skip on higher bands. It can also be used on VHF FM, and clearly has a much wider useful range of operating conditions that other more conventional digital modes. Sending speed can be varied between 20 and 60 WPM.

Screenshot of the ZL2AFP FSQCALL software with FSQCALL turned off

FSQ is designed for simple but effective 'Chat' operation, rather like phone text messaging or Skype™ chat; fast and easy to use. You don't use 'overs' as you would with a conventional digital or voice mode. It is highly suited to net operation. You just type a sentence and press Enter. 

An important factor in the design of FSQ is that no synchronising process is required to locate and decode the received characters. Lack of sync means that reception is much less influenced by propagation timing changes that affect almost all other modes, since timing is quite unimportant; it almost completely eliminates impulse noise disruption; and it also contributes to very fast acquisition of the signal (decoding reliably within one symbol of start of reception). Fast acquisition removes the need for addition of extra idle characters at the start of transmission, and this leads to a very slick system. Add high resistance to QRM and QRN, thanks to the low baud rate, and you have a system so robust that it does not need error correction. 

Sensitivity is believed to be about -13 dB SNR at 6 baud, and -16 dB SNR at 3 baud. That's about 10dB better and several times faster than 12 WPM Morse. 

FSQ is NOT compatible in any way with EXChat or DominoEX. While also a Chat mode, it uses a completely new and revolutionary protocol.


Direct download link -