Description
[virtual-signal=signal-1] A 1-9 can be made by combining four 1-3's.
[virtual-signal=signal-2] Observe that eight of the outputs come from two internal belts ([item=fast-transport-belt]).
[virtual-signal=signal-3] So we can just use a 2-8 instead.  The 2-8 doesn't function exactly the same as what was there before; in fact it disturbs the input balance.  But since we only have one input belt, the input is always balanced, so it's still a valid 1-9.