1- Did Vietnam ever received SA-2E system? They received it during Vietnam War?

No.
The 6cm wavelength S-75M Volhov (SA-2E) was available for the WarPact only.
The 10cm wavelength SA-75M Dvina (SA-2B/F) was available for other friendly countries. (Vietnam, Egypt, Syria, etc...)

2- Why russian designation for SA-2E and SA-2B are the same (S-75M)?

The designation is not the same.
nope

SA-75M Dvina [please remember, that the "A" means the "A" band - 10cm wavelength] (SA-2B/F)
S-75M Volhov [definitive version without the "A"] (SA-2E)

Last edited by Hpasp; 05/15/11 09:06 AM.
Hpasp
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