It's followed by numerous repetitions of the idle codeword. It's preceded by a preamble of alternating 1's and 0's that the receiver can grab onto, and a fixed synchronization codeword that tells where the data begins. There's no actual message being paged, just an 18-bit device address. The modulation is binary FSK, which means we should be able to directly read the data from the above demodulated waveform, even by visual inspection if necessary. Googling the device's model number, I found out it's using POCSAG, a common asynchronous pager protocol at 2400 bits per second.
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