What is the ruling on working as a maintenance engineer for radio stations that broadcast songs, music, and mostly trivial programs, and what is the ruling on the money earned from this work, given the difficulty of finding another job?

It is not permissible to work in the maintenance of broadcasting equipment that transmits forbidden content, because it entails assisting in the unlawful. One must repent and leave this work. "And whoever fears Allah - He will make for him a way out and will provide for him from where he does not expect." As for the money earned from this work, the preponderant opinion among the majority of scholars is that the contract is valid despite being forbidden. Therefore, there is no obligation to donate it or return it; repentance suffices.