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Discussion Starter #1
I am wondering if there is a way to trick my head unit into thinking that the MB phone is installed.<br>
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I am asking because I am working on a way to integrate just about any phone with stereo system. I have found a way to tap into the pre-wired microphone through the DB25 connector in the trunk and now I would like to try to tap into the DB25 pins for TX or RX Audio. With that, I will be able to use the stock microphone and audio input with a custom made connector plugged into my cell phone.<br>
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If I can fool the head unit into thinking that a phone is installed, when I hit the TELE button on the unit, the stereo should mute and activate the source for the TX or RX Audio on the DB25 just might pass to the amp.<br>
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Also, another question, does the MB phone system have some sort of a microphone amplifier? I notice that when I tap into the pre-wired mic, the sound levels for conversation are very low.<br>
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Thanks for any assistance.<br>
Khobalt<br>
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PIN DESCRIPTION<br>
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1 RX Audio<br>
2 Manual Test<br>
3 Negative Batt<br>
4 Positive Batt<br>
5 Red (N/C ?)<br>
6 TX Audio<br>
7 N/C<br>
8 Ext. Power<br>
9 Antenna Switch<br>
10 Red (N/C ?)<br>
11 Data Out<br>
12 Not Used<br>
13 D2B Fiber Wake-Up<br>
14 MIC Ground<br>
15 MIC Audio<br>
16 Positive Batt<br>
17 Negative Batt<br>
18 Data IN<br>
19 Brown (N/C ?)<br>
20 Brown (N/C ?)<br>
21 Batt Feedback<br>
22 Green (N/C ?)<br>
23 Ground<br>
24 Audio Ground<br>
25 N/C<br>
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Discussion Starter #2
The audio to the head unit is not carried over the DB25 cabling, it is carried over the fibre-optic (D2B) system ...<br> <br> The phone support electronics (pse) connects to the db25 and the fibreoptic, and talks 'D2B phone protocol' over the fibre, and motorola (in the case of the USA, Nokia in Europe) to the phone in the cradle.<br>
 
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