I need to be able to do the following:
At point A have a device (it must be a off the shelf product) that has a fixed voltage (anything from 12Vdc to 110Vac/dc) input that converts to a audio tone (any audio frequency that can be passed over a POTS telephone network) which is then passed down a telephone system (actually a PCM/CLG port).
At point B a device that will Rx the audio tone and while the audio tone is detected holds a relay closed, if the audio tone is lost or a fault develops where the signal is lost, the relay will open. The relay must be able to carry anything form 12VDC to 110VDC/AC to switch an indicator on a control/indication panel. The indications on this panel will be simple bulbs or LEDs.
There will be 20 indications (each its own Tx/Rx pair) in total.
Where can I buy such a device off the shelf (I can build my own but it MUST be a manufactured off the shelf product for my employers)?
Any ideas/help most welcome.
The audio tone is only an idea, what does the Pico enviromon network Tx over the 4 wires, could this be passed over the CLG port? If I had details I may be able to test it.