Random Problem

So uuh...

I was trying to make an Item Generator witch spawns an item every minute...

But... I don't know how to.

Idea:

1. The special information happens when the block is place

2. The block should do it, NOT the player

3. The item ^{(In dropped form)} should spawn every minute on top of the block ^{(Sorta like a dispenser/dropper)}

   Thanks for reading :)