This means that in order to get those tones to land in the desired location in the passband in FSL, you have to tune 1.500 KHz above the signal so in FSL mode, you'd actually tune to 8,474.500 KHz, a 1.500 KHz offset. Now, let's say you have your RTTY / SITOR decoder set up to expect tones centered around 1500 Hz. For FSK modes such as RTTY and SITOR, and for other modes like CW, in order to get the signal into the part of the passband you want in order to get the particular tone or tone set you want, you have to treat the carrier of the the signal as offset. The SdrDx demodulator frequency readout indicates the 0-frequency carrier point for the demodulator. If you prefer not to install soundflower, routing the audio outputs of your computer back to the audio inputs will also work, although now hearing the signal may be an issue. It's really just a matter of sample rate (and not all programs let you adjust that) and audio input selection. To use another program, just follow the above steps, but any step done for fldigi is instead done for the other program. I've had excellent results with RTTY, SSTV, FAX, CW, Packet, Olivia, and more.

Set fldigi to the 'native' sound data rate, select Soundflower (2ch) as the fldigi audio input, use the SND dialog to set the output of SdrDx to Soundflower (2ch), adjust the bandwidth in FSU or FSL to tightly surround the data signal, and enjoy. Once Soundflower is installed, start both SdrDx and fldigi. To use SoundFlower to route the output of SdrDx to fldigi:

So you can expect the waveforms on the RF spectrum to lead (occur in advance of) the audio you're hearing by quite a bit even if you've got LAT set down at 8 or 4.

Tip: When SoundFlower is the selected output device for SdrDx, it will add some delay, possibly even considerable delay, to the audio output.

Wlo rtty