User manual

VK2-2MPBX User manual V1.2
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- G.711, also known as Pulse Code Modulation (PCM), is a very commonly used waveform codec.
G.711 uses a sampling rate of 8,000 samples per second, with the tolerance on that rate 50 parts
per million (ppm). Non-uniform quantization (logarithmic) with 8 bits is used to represent each
sample, resulting in a 64 kbit/s bit rate.
- There are two slightly different versions; μ-law, which is used primarily in North America, and A-
law, which is in use in most other countries outside North America. G.711 μ -law tends to give more
resolution to higher range signals while G.711 A-law provides more quantization levels at lower
signal levels.
Audio Input: Adjusts the audio volume especially from the Mike.
Input volume: The Input volume can be adjusted in the range from -21.00 to 21.00 dB. The
default setting is 0 dB. Click the Mute box if you do not want the audio input.
Audio Output: Adjusts the audio volume especially to the Speaker.
Output volume: The Output volume can be adjusted in the range from -18.1 to 6.0 dB. The
default setting is 0 dB. Click the Mute box if you do not want the audio output.
- Click the Save button to save the settings, or click the Reset button to clear all of the information
you entered without saving it.