Thanks Hpasp!
When reading the manual again I saw things that scaped me the first time... Like: The Volhov series had added the optical channel later than the Dvina? Because looks like the first time Volhov had a TV camera was with S-75M3-OP, in 1983, but the Dvina had it since 1969, with the SA-75M Dvina “doghouse”. Or Am I wrong?

And I'm waiting for the answer regarding the S-300, if someone knows, please, I'd like to know