Hi friends.
I am looking for a circuit to recreate a telephone line. It will be used to connect an Alarm system to a GSM module.
When PSTN line is cut, then a relay will change the connection of the Alarm telephone line to the GSM. For the Alarm to work, it needs to see a telephone line and the GSM needs seperate Mic and Ear signals.
I found a chip that could do that, but others ideas are welcome. The chip is the STLC3055 from ST. It is small size and needs over 5.5Volts to work.
I'd prefer to work on 5Volts only with PDIP devices or even better discrete.
Thanks,
Ioannis
I am looking for a circuit to recreate a telephone line. It will be used to connect an Alarm system to a GSM module.
When PSTN line is cut, then a relay will change the connection of the Alarm telephone line to the GSM. For the Alarm to work, it needs to see a telephone line and the GSM needs seperate Mic and Ear signals.
I found a chip that could do that, but others ideas are welcome. The chip is the STLC3055 from ST. It is small size and needs over 5.5Volts to work.
I'd prefer to work on 5Volts only with PDIP devices or even better discrete.
Thanks,
Ioannis
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