The MPX3LCD is a detector that is designed to monitor up to 3 MPX signals and switch one of them to the output. The input that is active, i.e. the input that is switched to the output, is also shown at the display, and its audio signal can be listened to at the headphone jack.
On a failure of the main input, one of the other two sources will be switched to the output. The display of the device will indicate this with the text BACKUP: MPX1, MPX 2 or MPX3. This status is also shown in the HTML interface.
The MPX signals are switched through relays, so that there is zero influence on the signal.
On a detected silence, the priority of inputs that is switched to, is on the order of the lowest input number. For example, if inputs 2 and 3 are both present, then input 2 will always be connected to the output. With inputs 1 and 2, it is always input 1.
The status reports of this are done by means of emails and SNMP. All the settings can be made in the 4 HTML pages. These can be configured with a web browser (Firefox, Google chrome, etc.)
The detector also checks the 19 kHz signal. This is also shown in the HTML interface. You can choose whether the detection takes place by audio silence or the absence of the 19 kHz signal.
Preferable, use input 1 as the Main input. The reason is that on a power failure, the relays switches input 1 to the output.
At the back you can find the connections for the MPX inputs and the network connection.
There is also a 9 pin D connector with the text “Tally”
A relay contact is connected to this, which indicates the status of the detector. Pin 1 = NC Pin 2 = NO Pin 6 = common