For those not aware, this 6998 kHz outlet of the Buzzer signal appears to be an intentional parallel operation by the source. This does not appear to be a spur or an accidental transmission. It started on October 15, 2015, and has run continuously since then. There have been some changes with the signal, as are sometimes seen with 4625 kHz. Initially the 6998 kHz signal had no carrier, and a few days into operation it acquired a carrier, as commonly seen on 4625 kHz.
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