FSK transmit using flrig:
flrig can generate TTY Mark/Space signals on a DTR or RTS serial
port. That serial port can be either
- shared with the CAT data-in/data-out port, the IC 7300 for
example
- on a separate transceiver serial port, the FT 991A for example
(sorry no screen shots)
- shared with the auxiliary serial port,
- or via a completely separate serial device, USB or a part of
the computer. Amazon sells USB serial devices which can
be used for both CAT and FSK keying.
CAT interface cable
USB serial to key-line interface. Connects to the
transceiver FSK Mark/Space input. This may require a
change from the 3.5mm stereo plug to one compatible with the
specific transceiver
FSK transmit using fldigi:
fldigi has several methods by which a transceiver can be keyed in
FSK:
- as a digital audio waveform in the same manner as transmitting
PSK, MFSK or any other digital signal
- set transceiver to USB or USB-DATA
- select RTTY as operating mode
- use the waterfall to select the transmitted audio injection
frequency
- use transmit text panel, the T/R button, macros, and/or the
Pause/Break keyboard button to generate and send the FSK
signal
- advantage is that the RTTY can be sent at any point on the
waterfall. Rx and Tx can be at separate audio
frequencies. RTTY transmitted signal can be typical
broad band MARK/SPACE signalling or with signal shaping to
reduce FSK side bands.
- disadvantage is that transceiver narrow band RTTY filtering
might not be available, but narrow digital filter may still be
available
- detection of a stereo right channel on/off keyed audio signal
with conversion to a hard line keying signal
Note that the right audio channel can be used for either the FSK
keying waveform or a QSK control signal, but not both
simultaneously.
- as a DTR or RTS control line
- Note that you can interface to the shared CAT port (IC
7300), or a separate serial port (FT 991A and QCX+)
- Check the "Enabled" button
- Either share the RigCat seria port or a separate serial port
- by interface to the flrig FSK keying system
- configure flrig to send FSK as per the flrig stand-alone
instructions
- set transceiver to RTTY mode
- disable all other fldigi RTTY generation schema
- enable the "Use flrig FSK keying" button
- by interface to a stand-alone FSK terminal unit such as
nanoIO, MORTTY, WinKeyer3, or US Navigator.