NDB - non directional beacons from Cuba (or possibly Cuba) :
NDB Camaguey *UMC CUB-890 NDB Cayabo *UCY CUB-210 NDB Cayo Largo del Sur *ULC CUB-248 NDB Playa Baracoa *UBP CUB-264 NDB Santa Clara *USC CUB-269 NDB Varadero *URV CUB-274 NDB Zaragoza *UZG CUB-215 NDB unid, possibly Cuba *UBC ? ZZ-2534 NDB unid, possibly Cuba *ULV ZZ-2582
Cuban NDBs seem to have very low effective radiated power - the signal of 'URV' was received in about 30km distance with the same signal strength as 'CBC' from the Cayman Islands - a distance of 400 km. 'DDP' from Puerto Rico, known as a powerhouse, got a 7dB stronger signal than 'URV', from a distance of 1600 km...
All the other cuban stations also had a low signal level.