I am going to move this thread to the Utility forum, since that probably fits the signal a bit better. If you read the Read Me post at the top of the Mystery forum you will see that that forum is really intended for mystery modes, vs source identification.
With that said, get set up to do audio recordings of signals. Without more detail than you have provided it is unlikely you will get a meaningful answer. An audio recording goes a long way to confirming a signal type.
Here is the problem, are you sure it is really CW you are hearing? There are several possible signals that operate around that frequency, and none of the better candidates are Morse code. FSK, various digital modes, and Link-11 are the most likely.
If I had to guess, I would say you are hearing the Doppler tone of a Link 11 signal. There is a relatively active Link 11 on 11016 kHz USB, this would put the Doppler tone on 11016.605 kHz, or at about 1605 Hz audio if you tuned to 15015 kHz in USB mode. So you might hear short and long pulses, that can be mistaken for CW. The fact you are hearing only U’s, V’s, and 4’s can support the Link 11 possibility, it can sound something like those characters under some conditions.
T!