Encoded Media hardware encoder appliances automatically broadcast the availability of multicast channels via the means of SAP announcements.
Announcements are broadcast on multicast group 239.255.255.255 port 9875. Testing for these packets is a simple, two step process using McTest.
239.255.255.255:9875
into the IP address field at the top and tap Start.You are looking to see SAP announcements shown in the Quality bar at the top, as below: