http://breezewiki.catsarchywsyuss6jdxlypsw5dc7owd5u5tr6bujxb7o6xw2hipqehyd.onion/minecraft/wiki/Block_of_Redstone
A block of redstone: powers any adjacent redstone dust , including above or below, to power level 15 powers any adjacent redstone comparators or redstone repeaters facing away from the block of redstone to power level 15 activates any adjacent mechanism components ( doors , redstone lamps , etc.), including above or below, with the exception of pistons , which cannot be activated by any power source...