said by aurgathor:said by cowboyro:I want to use multiple phones in the house. While hacking one is acceptable, when I'm considering 6 phones it's no longer OK
I see. For that much of a load, you probably need an amplifier.
I was hoping lutful will post a transformer-less DSP solution -- but he seems to be slacking....
I was waiting for someone to actually post a convoluted analog POTS interface circuit that manipulates just the audio without impacting ring waveform and off-hook detection. Good quality telephony devices designed since 2005 actually use transformer-less POTS interface and include DSP.
Above block diagram shows how you can make a digital FXS-FXO repeater using off-the-shelf SLIC/DAA ICs and a DSP or FPGA that could do any kind of manipulation of the audio and DTMF. But AFAIK such a device does not exist but VoIP gateways that also have a proper FXO interface could be hacked to do this job.
cowboyro
... If the Magicjack is connecting to all the phones in the house, the "ring equivalent number" or REN seen by their line driver IC could be too high.