ETOPS
Here is a link to the Traffic Awareness Beacon System (TABS) requirements under TSO-C199. TABS was designed as a standard for
certified ADS-B In to receive - ie. ATSAW, CDTI, ACAS-X, etc...
https://www.icao.int/APAC/Meetings/2...20briefing.pdf
To save you wading through it, here are the parameters of interest:
Someone mentioned SkyEcho. This Low Power ADS-B Transceiver (LPAT) can do SDA=1 and SIL=1 and does so in Australia under the Australian regulations. It also has a TSO-C199 GPS and so it has everything needed for the UK once the CAA allow it under CAP1391 and people enable SDA=1 via the software. At £250 after the CAA rebate, then it’s a ‘billy bargain’.