In November-December a Latin American station below the 1200 kHz channel was noted and it seems the split was a new one or I had not noted it anyway earlier. Finally when I got some audio it seemed there was a Spanish station with talk programming around 06-07 UTC and there was indeed some IDs at around 6 and 7 UTC. When I first listened to the clips it all sounded something like "Radio U" which was something like (maybe) "U Radio" from Ecuador. However, when HK checked the clips he immediatly answered to me "it is Cucú Radio"! Well, I had been looking only to the lists of South America and did not think it could be from Costa Rica as if I remember right I have never got anything from Costa Rica on medium waves ! Anyhow, the id seems to be "Radio Cu Cú - tu Radio"!
Since then the station seems to be there fairly often at least with the carrier visible (and some sudio also in January). This is a bit hard channel during good conditions as there a other stations usually also and La Voz de la Raza from Colombia on 1200.17 makes sometimes a big het here. Cucú has been on 1199.880 so LSB has to be used when listening to it.
Thank You Henrik once again for the work with this one. The station seems to have a web-page but unfortunately the audio stream is not working.
Saludos a Radio Cucú San José!