Hotfoon - Nodes Audio Cables

Nodes Audio Cables

To run a GSM/CDMA node you need two cables.

1. A Data cable to control the dialing and hang-up.(To know more about data cables, read the Installation instructions).
2. An audio cable for voice.

The PC’s sound card is connected to the phone’s handsfree socket through the audio cable.

Making the audio cable is very easy. Anyone with basic soldering skills should be able to make these cables for you.

Node Cables

Tips:

1. Buy a Motorola handsfree, cut the cable between near the mic and solder the two audio jacks (use different colored jacks).

2. Use a VOM/Multimeter to check that the connections are as per the diagram above.

3. Keep the two jacks of different colors to differentiate between the mic and speaker jacks.

Testing the cables

You need the help of a friend to do this testing.

Step 1: Connect the cable to the cell-phone and the PC sound card.
Step 2: Start the sound recorder from Start->Programs->Accessories->Entertainment.
Step 3: From the cell phone, dial your friend’s phone number.
Step 4: Press record button on the Sound Recorder application.
Step 5: When you friend answers the phone, the Sound Recorder Display should show the voice patterns.
Step 6: After a few seconds of recording. Press the Stop button and then play back the sound by pressing the Play button.
Step 7: Now the friend should be able to hear their own recorded voice. The voice might be slightly distorted (that is okay).

If this doesn’t work, check the connections. There are two things that usually go wrong:

1. The leads might be swapped. The ground wire could be connected to the tip and the signal to the ring.
2. Check that the jacks are properly connected to their respective sockets on the sound card. That is, the mic jack to the mic socket and the speaker jack to the speaker socket and not the other way.