User's Manual

WiNRADiO G39DDC User’s Guide
122
Appendix G – Recording File Formats
The DDC recorder can record the DDC stream in a standard WAV file format,
but saves the files with an extension “.ddc” in order to avoid confusion with
audio wave files. The proprietary WiNRADiO RXW file format (extension
“.rxw”) is often a better choice, because it also contains additional data such
as the current DDC center frequency, date, time and internal compensation
data, which makes it possible to simulate original conditions during the
playback. When replaying an RXW recording, the recorder panel shows the
original time of the played back signal and the DDC spectrum scope shows the
original DDC frequency. If “Waterfall timestamps” option is enabled, the DDC
waterfall also shows the original time in its vertical axis.
All DDC files are stereo (as they are stored in the I/Q form) and 32 bit, except
for 3.2, and 4 MHz DDC bandwidth which are 16 bit (due to limited USB
transfer rate). The recording sampling rate varies according to the selected
DDC bandwidth, shown in the following table:
DDC Bandwidth
(kHz)
DDC Recording
Sampling Rate (kHz)
20
25
24
32
32
40
40
50
50
62.5
64
80
80
100
100
125
125
160
160
200
200
250
250
312.5
320
400
400
500
500
625
640
800
800
1000
1000
1250
1250
1666.67
1600
2000