On interfacing to the handset interface of the phone, those links could be useful:
Headset-Adapter for Cisco-IP-Phone
http://www.mml.uni-hannover.de/einhorn/ ... dex_e.html
- Code: Select all
Western-Jack 1 2 3 4
Color (e.g.) black red green yellow
Signal SPK+ MIC- MIC+ SPK-
Speaker jack L+R ground
Microphone jack ground L+R
pinout for"standard"telephoneheadsetrequired.?
http://lists.digium.com/pipermail/aster ... 00099.html- Code: Select all
RJ10 -- 2.5mm
1 3 speaker ground
2 1 mic
3 3 mic ground
4 2 speaker
In addition to those you need some wireless radio links for the audio. Those can beascally work at wahtever frequency band you are allowed to use. You need one bdirectional link that can transport audio to both directions, or two unidirectional links (one for telephone to headset direction, one for headset mic to telephone) operationg at different frequencies (can ba channes some distance aways from each other on some band or at completely different band).
The radio links should be able to pass the telephone frequencies (300 Hz to 3400 Hz) at reasonable quality..
Depending the application needs those can be anything in the following line:
- some existing wireless headset product maybe made for some other application originally (as long as it has mic and speaker connections)
- small FM transmitter circuits (1-2 transistors) + normal FM radio on the receiving end
- walkie-talkie radios
- wireless audio links (wireless monitoring systems, wireless "hifi" audio links, wireless microphone products etc..)