What kind of propaganda was it? Do you remember much about the messaging? Were they broadcasting outright lies, like classical agitprop? Or was it primarily white propaganda (truths the Cuban government rather its people not hear)?
The Radio Americas programming was a not-so-covert CIA promoted anti-Castro message all day long. It was done by exiles in Miami who had been in radio before the revolution. The main messages were about the people still in Cuba who opposed the Castro regime who were still alive and either sanctioned or in prison or those killed or "disappeared" by the Castro government. The content included things about the confiscation of property, the totalitarian government restrictions, the growing population in the political prisons and such.
It was what you call "white propaganda" done by people who had to flee their homeland... people who had seen their family members killed or imprisoned... people whose homes and possessions had been "nationalized".
I'm an honorary member of the Association of Cuban Broadcasters in Exile so I know a lot of the story.
Also as soon as I saw your quotes on the word "owned", I instantly thought to ask whether you felt it may have been a CIA front. But your answer came as soon as I read your subsequent post. Sounds like the kind of adventure that would have been fun as a kid in deed, but a little alarming to think back to from the perspective of an older, wiser adult.
No different than having my own station taken over, briefly, by guerillas, or ´being beaten up on the street in other points of my career. Oh, and having the building I was in bombed by the Sendero Luminoso in Perú...
Do you suppose it goes without saying that anything Cuba had for successfully interfering with American broadcasts was being supplied by the Soviets?
Even the transmitters were built by and installed by Russia. In the later 60's, the manufacturer of those Russian transmitters tried to sell them throughout Latin America. On one occasion, I was visited by a "sales rep" offering me the 60 kw and 120 kw AM transmitters at amazingly low prices. The salesman was, of course, Russian. But he was accompanied by a silent guy in a classic ill-fitting Russian suit who just watched what went on... obviously KGB to the core.
At the time, I believed in lower power stations in each market, not national or regional signals so I did not buy a Russian Svetlana rig with way too much power and with proprietary "only from the USSR" tubes.
"You will buy our transmitter, yes? Or else we will be having to shoot you."