Cellular phone line
Budget: $750 – $1,500 USD
I'm searching for a device that would accept a sim card and operate on the 4g GSM network. This device would provide a "pots" or "tip and ring" output. It would need to accept incoming DTMF tones from the receiving part and from the connected dialing device. It will also need to provide line voltage or simulation. Ideally it would have an antenna port for an external antenna.