This device helps the operator notice incoming calls when working in very loud environments where the regular call coud go unnoticed. The unit includes a buzzer which can be switched on/off by the user and also remotely from any ALTAIR base station.

This device is connected to the intercom line same way as a cable beltpack, with one XLR3 connector to "receive" the signal and another XLR3 connector to continue the intercom line to the next beltpack.