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I have been performing several weak signal tests using the DMR mode.

One of three things seems to happen when a signal gets weak.

  1. Audio is completely dropped for duration of weak signal.
  2. Audio becomes distorted and garbled giving the "R2D2" sound due to high bit rate error.
  3. Audio frame snippets are repeated several times like a broken record.

I understand why case 1 and 2 happens, but I am confused on the repeated audio packets. Could this have to do with the receiver "waiting" for the signal to come back as an attempt to make up for what is lost? If so, Why does it only occur occasionally on weak signal dropouts and not every time?

In this example, the audio is completely lost before the repeating occurs: Audio Snippet Link

The hardware on both ends is the TYT MD380

Skyler 440
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1 Answers1

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Repeating the last frame to fill in holes from missing frames is a common digital voice technique. For small rates of frame loss, repeating a frame now and then is less noticeable than silence.

Phil Frost - W8II
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