Hytera RD986 - Page 24

Service Manual
6.2.14 Audio Path
The audio path is used to relay audio, output RX audio and input TX audio.
6.2.14.1 Relay Audio Path
After demodulated by AD9864, RX audio in digital/analog mode goes to RX OMAP. Then the audio is
sent to TX OMAP via McBSP3, and finally is subject to DA conversion to modulate VCO.See the
following figure:
TX
OMAP5912
U102
RX
OMAP5912
U202
DAC
TLV561
U304
MOD
AD9864
Q
McBSP2
McBSP3
McBSP2
21
Figure 6-21 Relay Audio Path
6.2.14.2 RX Audio Path
ntrol the audio output of Slot A from SPK1 and that of Slot B from SPK2 via
01)
output filtered audio or flat audio (RX_Audio) to
Figure 6-22 RX Audio Block Diagram
In digital mode, Codec can co
the left channel and right channel respectively, and select the time slot required for local audio
monitoring via the switch Slot1_EN. Meanwhile, under the control of Slot1_EN and Slot2_EN, the
outputs of Slot A and Slot B are sent to PIN24 and PIN25 of the further development port DB26 (J7
for further development.
In digital mode, SPK1 of CODEC can be configured to
the further development port DB26 (J701). The filtered audio from SPK2 is output to the speaker to
realize local monitoring via the audio amplifier or to the audio port of the front panel via the filter. See the
following figure:
MMP10_SPK_Audio
CODEC
U501
SPK2
U502
TDA8547
SPK1
RX_Audio
Slot A
DB26_PIN24
DB26_PIN25
McBSP3
RX
OMAP5912
U202
McBSP2
Slot B
RX _Audio_Mute
Slot1_EN
RX
AD9864
Audio_PA_EN
Slot1_EN
Slot2_EN
TX
OMAP5912
U102
McBSP1