Not sure if this has been discussed, but if I equip a Seismic Charge and Proximity mine on a ship, can I drop the Seismic when I reveal a manever and then us my action after the maneuver to place the Proximity mine?

No. They're all classified in the game as "bombs" and only one per round.

Rules Reference Guide - Page 7

Thanks.

Note, you can drop a bomb/mine and use other ordnance in the same round, like shooting a missle. I know the question wasnt asked by OP, but might be useful to someone looking.