A filter inserter picks the mixture 1 u-235 and 19 u-238 from the belt.
The filter inserters are controlled with the combinators.
If you send iron plates it will produce uranium fuel cells.
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This works a very long time. Sometime the balance is disturbed.
So I use a belt stop detector, which sends a warning.
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+pUEJdw0CZ2dy4tHQnlMRKXQKczAL/XOcdX0+LS/qJzFwnzKsG41OY46LVr1fenkiUvt///nviRMe9F5u4At2KvAy4J2AgWM0Q/Dj+rVJvFdDw6uAzXfMf37zfoVeUjLlTME5TPIDMbJ6Ov8V+OHZTX8pTOxrqGU1jYVMpaC7edCiGJqoku9pUafdaNlJ82A2RTUhWAsOwDrRno6+VMsPxC/Bh1COpsVJLQNhBwnOA8ghJX/ZF6+52dzkW7upsqI9B3uwVb0Pio2LlONEK80iJdXT0/8BOQwvmA==