Never been involved, but something a bit more that "1605" seems constructive ... "Antonov squawking 1605 this is interceptor L9T47" might be a good start, to give them a clue about the disembodied voice in their headsets. Cryptic, clipped, Mil R/T might work with the 'mates' on frequency, but dealing with foreigners requires a little more to achieve 2-way. Done a fair bit of non-standard comms in my ATC time when controlling other Nations, especially non-English native speakers.