The transmitter is sutured to just outside the vulva approximately 1-2 weeks prior to the expected due date. The physical separation of the vulva lips pulls the actuating magnet from the transmitter. When this occurs, a silent radio signal is sent to the receiver which then 1) sounds an audible alarm and 2) activates any accessories attached to the receiver. There are two kinds of transmitters, the Multi-Use (blue) and the Single Use (red). The Multi-Use transmitter can be used up to ten (10) times, depending on the length of time that the magnet is out of the transmitter shelf. The Single-Use transmitter is used only once/ then thrown out. Both transmitters work with either the Standard Range or Long Range receiver. You may monitor multiple births simultaneously, provided each expectant mother is wearing a transmitter and is within the tested range of the receiver.
