Well I'm excited to present this to you, the Minecraft community:
THE WORLD'S SMALLEST REDSTONE CLOCK WITH NO COMMAND BLOCKS!
Not much to explain but it includes just 2 observer blocks that are facing towards each other!
Well if this was already made, I'm sorry, I didn't know... xD
If it doesn't work for you, then just add a repeater set to two ticks at the end of the redstone dust.