DSP offset

kb9zm

What dose DSP offset for?

KD0RC

The DSP offset moves your receive passband so that it centers on digital signals. I don't think it is working just right with the latest release of SmartSDR, but since they added the ability to edit your filter parameters by mode, it is easy enough to plug in what you want. For me, when using VarAC on DIGU, I set my 600 Hz filter up to center on 1500 Hz (1200 to 1800). This perfectly centers my RX signal in the passband.

Mike-VA3MW

35.6 Digi Mode Audio Offsets

When operating the radio in DIGU or DIGL mode a receive filter Offset control is available in the DSP tab of the Slice Receiver. This control allows the operator to set the audio offset in Hertz of the center of the receiver’s bandpass preset filters. When click tuning a Slice Receiver with an Offset set to a non-zero value, the Slice
Receiver’s frequency will be adjusted so that the center of the receiver’s bandpass filter will be tuned to the
frequency that was click tuned. The default offset for DIGU is 1500Hz and the default for DIGL is 2210 Hz.

However, since our audio bassbands in DIGI modes are flat it really isn't required for FT8, etc.