Q&A for How to Make a Redstone Dispenser Loop in Minecraft

Yes, both droppers and dispensers work, although droppers are recommended since it can drop out all items.

No, you can fill it with any item! Be aware that if you put something like a spawn egg in, it will spawn something, not release the egg.

Because when you put the Redstone Torch on the dispenser (or dropper) it wouldn't work. To do this you need to squint, and then put the Redstone Torch down.

This varies greatly on what type of server. If you want to do something semi-professional, or to support server-side mods (such as world-edit, mini-games, etc.) then look into Spigot or Sponge (in-dev). Otherwise, you can grab a copy of the official server (Vanilla) from the Minecraft website.

No. You just have to place a large stack in the dispenser. It doesn't really matter how many you put inside; just put in as many as you want.

No, that is called an item dupe and those are hard to make. So, no it will not multiply the diamonds, just give you as many diamonds as you put in the dispenser.

The Nintendo Switch is an unsupported platform, it is rather newer, so this is not supported yet. This should be added/fixed soon.