3 ms·
Just a small nit, most of those are FSK but PSK31 and it's variants are actually Phase Shift Keying[1] which is pretty cool in its own right. Rather than changi
by vvanders 9y ago
Just a small nit, most of those are FSK but PSK31 and it's variants are actually Phase Shift Keying[1] which is pretty cool in its own right. Rather than changing frequency it's a shift of phases when combined with a 90' signal(often called quadrature, hence I/Q signal you see in SDRs) you can encode more than one bit per symbol.
Either way it's pretty cool stuff.
[1] https://en.wikipedia.org/wiki/Phase-shift_keying https://en.wikipedia.org/wiki/Phase-shift_keying
- vvanders 9y agoAlso forgot to mention it but an even wider use of AFSK than FT-8 and it's WSJT cousins is AX.25/APRS over VHF. Sadly it's not nearly as advanced as FT-8 since it most commonly uses 202 Bell tones and a blazing 1200bps. There's been other digital formats but the whole situation is pretty fragmented. The infrastructure side of APRS is pretty nifty, you have sites like aprs.fi[1] that let you see the current state of the world in near realtime anywhere an I-Gate is present. [1] http://aprs.fi/ http://aprs.fi/