Wavecom W74PC V8.7.0 - Manual (Page 40)

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First start WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V8.7.0
The WAV file format supports files up to a maximum size of 4 GB. The maximum length of recording that
can be made depends on the sample rate, number of channels and bits per sample. The table below lists
the maximum recording lengths for a few common formats:
Format Max recording length
8kHz, 8-bit, AF 149 hours, 7 min
8kHz, 16-bit, AF 74 hours, 33 min
48kHz, 16-bit, AF 12 hours, 25 min
48kHz, 16-bit, IQ 6 hours, 12 min
192kHz, 16-bit, IQ 1 hour, 33 min
Playback Controls
Sound playback can be routed to the output of any installed sound card. To select the sound card that will
be used for playback, use the Output Device control:
Monitor Function
The monitor function allows the user to listen to the audio signal connected to the sound card input.
Press the Monitor button toggle this function on and off.
The monitor function works by playing back the recorded signal in real time. A circular buffer is used re-
sulting in a small delay between the input and output signal.
A problem may occur when monitoring an input from one sound card to an output on another sound card,
where the sampling clocks used for the input and output will not be synchronized. On some sound cards
different clocks are used for input and output, resulting in the same problem. In these cases the monitor
function may produce sound with occasional skips and interruptions - this is normal, and will not affect the
integrity of recorded sound.
Some sound cards have an input labelled something like “What You Hear” or “Wave Out” allowing the re-
cording of sound produced by other applications on the computer. When these inputs are selected, the
monitor function should not be used as it will create a feedback loop.
Record a Signal from Wavecom Hardware Devices
Media Player/Recorder can also be used to record a signal on a Wavecom hardware device, including W-
CLOUD. This is done via Wavecom Virtual Audio Cable (W-VAC). User can select W-VAC as the “Input De-
vice”, the signal on a Wavecom hardware device is redirected to the W-VAC and thus can be recorded by
pressing the “Record” button. The signal format is IQ in general; for audio signal one channel (Left or
Right) is just of zero value.