On the manual, S-300 is part of Volhov family, and it's development looks related to the development of 6cm antennas and systems of S-75M3 Volhov.
My question is: In what degree the development of S-300 is related with the S-75M3?
The S-300P is a completely new system,
developed using the lessons learned during the Vietnam War.
When the first S-300P version, the
S-300PT Biryusa (SA-10A Grumble) fielding started, the development of the S-75M4, and the S-125M2 was immediately scrapped.
