7/24/13 2158z 10715 KHZ

[Tim537]

Female VX in SS.  Very poor signal with a lot of noise.  Signal ceased at 2200z.

[Token]

How sure are you that it ceased, or might you have made a mistake converting to UTC?

The reason I ask is that Spanish language hybrid numbers station HM01 is scheduled for that frequency in the 2200 hour.  It normally starts about 4 or 5 minutes early, so say 2156 or so.  It starts with 5 figure groups sent for several minutes, and then it goes into a voice / digital alternating pattern.  This often starts about 2200z, and generally continues until about 2255z.

Is it possible you heard the lead-in voice, then the transistion to the first digital, and assumed the voice was done?

T!

[Tim537]

Hmm.  Not saying you are wrong, T!, but I did listen on for some twelve minutes. Even ran the tape in case I had to leave the room for anything. Nothing more was heard.

[Token]

I am not wrong...I guarantee that   But the reason I am not wrong is not because I am right, only that I was asking the question of if there was a possibility that the station had entered a different mode.  I was not saying it did, only asking for confirmation that the signal went away instead of changing.  If you listened a further 12 minutes (even just a couple more minutes) and did not hear an alternating voice and data pattern then you have confirmed it.

With the HM01 station, indeed any of the Cuban stations, anything is possible.  Errors at the station are common, and you easily could have heard exactly what you describe, no question.  But it did not fit the known schedule, so I suggested an option that could explain it.

What you probably heard was the beginning of the normal 2200 z HM01 transmission (normally on that freq and starts a couple minutes early), and then the station had a technical problem and did not continue the transmission.

T!

[Tim537]

Many thanks for sharing knowledge and experience! Your explanation sounds very plausible. I plan to return to that f and monitor some more.