Motorola PMMN4092 Handbuch Seite 6

Digital Symbol
Figure 3: Digital Symbol Marking
Radios with this "Digital Symbol" are digital
capable radios and require the use of accessories
with the same "Digital Symbol". These
accessories with the "Digital Symbol" have been
optimized for digital audio Transmit and Receive.
Use of non-approved accessories may result in
degradation of audio quality.
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