There are many other sources of rAD other than salvage. However, rAD earned this way is stuck on one character until it is refined.
Daily Dungeon - The first two dungeons completed each day on a character reward a small sum of rAD. Both leveling dungeons and epic dungeons qualify for this. This can be done on multiple characters each day
Daily Skirmish - The first two skirmishes completed each day reward a small amount of rAD. Once again, both regular and epic skirmishes qualify for this, and it can be completed on multiple characters each day
Daily PVP Match - The first two PVP matches completed each day reward a small sum of rAD. Can be completed on multiple characters each day.
Invocation - A character can invoke up to 8 times every day. Each successful invocation will reward slightly more rAD than the last. The amount of rAD received from this also scales with level. Many players have a large “army” of alts that they invoke multiple times a day for the rAD income.
Weekly Campaign Quests - Sharandar, Dread Ring, Tyranny of Dragons, and Icewind Dale all have a weekly campaign quest that rewards 4500 rAD when completed at neverwinterstore.com.
Other Sources of Rough Astral Diamonds neverwinter (344 previews)