Hi All,
To provide LTR, Passport, and Multi-Net support to Unitrunker this thread was created to design an external low pass filter.
In another thread, Unitrunker suggested that an external low pass filter may be developed that connects between the discriminator audio and the sound card input. The sound card's left channel would input unfiltered discriminator audio and the right channel low pass filtered audio.
This would not only allow adding the 3 protocols to Unitrunker, but having the filtered data would be helpful with reading the low speed data on Motorola and EDACS voice channels and would allow for a more efficent way to leave the voice channel more quickly.
The low pass filter can be created by using op amps or by using a filter IC chip such as:
http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1154,C1008,C1148,P1356,D3153
Again this would be a filter design only (not a filtered data slicer). We would need to agree on what the proper cutoff freq be, type of filter (butterworth, bessel, etc), and other details.
What do you tech guys think about this?
thanks,
To provide LTR, Passport, and Multi-Net support to Unitrunker this thread was created to design an external low pass filter.
In another thread, Unitrunker suggested that an external low pass filter may be developed that connects between the discriminator audio and the sound card input. The sound card's left channel would input unfiltered discriminator audio and the right channel low pass filtered audio.
This would not only allow adding the 3 protocols to Unitrunker, but having the filtered data would be helpful with reading the low speed data on Motorola and EDACS voice channels and would allow for a more efficent way to leave the voice channel more quickly.
The low pass filter can be created by using op amps or by using a filter IC chip such as:
http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1154,C1008,C1148,P1356,D3153
Again this would be a filter design only (not a filtered data slicer). We would need to agree on what the proper cutoff freq be, type of filter (butterworth, bessel, etc), and other details.
What do you tech guys think about this?
thanks,