Hardware Interfaces
FOX3-2G/3G/4G Series Hardware Manual
46
Figure 27:
Audio plug 4pin connector
To know the pinout of the audio jack on the FOX3-2G/3G/4G-AUDIO, see table below.
Pin
Pin name
Description
Pin
Pin name
Description
1
MIC
Mic -
3
MIC
Mic +
2
R_SPKR
Right audio speaker
4
L_SPKR
Left audio speaker
The following table lists some typical electret microphone electrical and speaker characteristics
when connecting them directly to the FOX3-2G/3G/4G-AUDIO audio interfaces:
Microphone
The microphone should be a electret condenser microphone @ 2.2 k.
Speaker
The speaker should be a passive headset with 8O ohm or an active speaker with symmetric
balanced input. Asymmetric non balanced input will cause GSM noise in the speaker.
We provide an adapter cable (called "
CA81b
") with an integrated transformer that provides a full
galvanic isolation between the FOX3-2G/3G/4G-AUDIO audio interfaces and your loudspeaker. It
allows connection to any loudspeaker on the market. If you would like to use this audio adapter
cable, then you need to order it using the order designation "
CA81b
".
Figure 27.1:
CA81b - Audio cable with integrated transformer provided by us
