20 May
2018
20 May
'18
9:24 p.m.
At 11:35 AM 20-05-2018, nokoa3116(a)gmail.com [op25-dev] wrote:
Do the tones not go like voice over radio.
Generally, no.
Is it like a code that the scanner then changes into
a beep?
Yes. Tone frames encode a frequency index and a volume level. A
receiver has to synthesize the indicated tone/volume for 20 ms per frame.
Page 20 has a list of AMBE tones:
<http://qsl.net/kb9mwr/projects/dv/codec/TIA-102.BABA-1%20%20P25%20Half%20Rate%20Vocoder%20Addendum%20.pdf>
A slightly different list is found on page 58 here:
<http://dvsinc.com/manuals/AMBE-2020_manual.pdf>
IMBE tone frames are likely similar.
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