Prisoners of Power

Strugatsky, Arkady, and Boris Strugatsky. Prisoners of Power (vt. Inhabited Island, Russian: Обитаемый остров, romanized: Obitaemyy ostrov). Neva nos. 3, 4, 5: 1969 (publication of the Leningrad Division of the Union of Soviet Writers). Book 1971, "with great number of changes as demanded by the state censor." Helen Saltz Jacobson, translator. New York: Macmillan, 1977.[1] Introduction by Theodore Sturgeon. New York: Collier, 1978. New York: Penguin, 1983.[2]

In Wikipedia summary, there are towers on a non-Terran planet, where a controlling elite — "Fire-bearing Creators" or "All-Powerful Creators" or "Unknown Fathers" depending on censorship and translators — broadcast

a mind control signal, employed by the Fathers to control the population.

The constant low-intensity broadcast suppresses the ability of most people to evaluate information critically, making the omnipresent regime propaganda much more effective. In addition, twice a day an intense signal relieves mental stresses caused by the disconnect between the propaganda and the observed reality by inducing euphoria in the susceptible majority, and intense headaches in others who are immune to the signal's coercive power. Those are the only sober-thinking people in the country, including both the underground degens [degenerates — the opposition] and the Fathers themselves.[3]

John J. Pierce notes that such mind-control is "an old concept in Soviet sf, going back to Belyayev’s Ruler of the World (1929)" (Foundations of Science Fiction revision, in ms. Soviet SF p. 23).[4]