Twenty hive honey block farm

An automatic honey block farm of twenty beehives, designed and built by aJack. Every hive has its own dispenser holding a glass bottle, and a composter held at level four acts as the signal source that tells the module when to fire. The full honey bottles run down a hopper line into a single crafter, which turns every four into a honey block, and a chest minecart on rails carries the empty bottles back around to refill the dispensers so the glass never leaves the system. An anti overflow section keeps the honey block storage from backing up. It has to stay chunk loaded, and the video covers building it on the nether roof or in the End where the bees never stop for night or rain.

Empty the honey out of the hives before you place them. A hive that is already full never fires its observer, so that module never starts. bradychristensen4837 and kufe2 both trace failures to this.
The composters are signal sources held at level four, not compost bins. Leaves only raise the level 30 percent of the time and cake raises it every time, which is what caught fenris1029 and simeonblair2991 out.
If one section stops collecting, look for a comparator behind the hives with both torches lit. Take the glass bottle out of that dispenser, harvest the hive by hand, put the bottle back and it restarts. That is jimakys's fix.
Close the bees in with stairs rather than slabs. HiWhatsup-j5c on 26.2 and Im_KrazyDude both had bees escaping through slabs.
If the bottles never get refilled into a dispenser, break the redstone dust on the back side opposite the minecart. Building out of order leaves that line stuck on, which AshtonApolinario found.
On Bedrock, admchin rebuilds the bottle elevator: swap the block next to the bottom dropper for a target block with a building block beside it, put another target block on top, and redstone everywhere else including on top of the second target.