This system is used by Israeli Navy, more likely from 4XZ station in Haifa, and it's quite easy to hear. The waveform is composed of 3 parts: a four tones (2 seconds length) preamble, the parallel-data part using QPSK modulation in channels at 75Bd speed and the final serial-data part according to the MIL 188-110 single tone (1800Hz carrier modulated with PSK-8 at 2400Bd). A variant with an added 230ms pre-tone at 1000Hz has been seen.
Since the low data-rate, the apparent ACF is 66.6 ms.
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