A new version of the RFzero library has been released. It includes the new FST4W narrow digital mode with its four sub-modes. This enables the RFzero GPS controlled RF source to send FST4W as a stand-alone transmitter.

The RFzero is a multi-purpose GPS controlled RF unit. It can be used as a beacon (IBP, SPB, CW, FST4W, FT4, FT8, JS8, JT9, PI4, WSPR, …), signal generator, VFO, QO-100 dual LO, low-cost GPSDO, e.g. for 10 MHz or 49,152 MHz for the IC-9700, or … Furthermore, is the RFzero an Arduino compatible platform. So it is possible for you to write or modify the software yourself.

More than 20 programs, Arduino sketches, are integrated into the Arduino IDE for easy upload to the RFzero.

RFzero Library - https://www.rfzero.net/