15 bit ÷ 11 bit - part the first

This is the big one: a direct implementation of the unrolled non-restoring division algorithm. A total of seventy chips, including no fewer than forty-eight 74LS181 arithmetic logic units!  

All these chips are organised across six main boards; five of these (which are identical, each dispatching three lines of the long division, and having nine 74181s), are stacked over a base board. The latter (with three 74LS181s) handles the final step of the non-restoring division, namely calculation of the remainder. This board also has the TIL 311 hexadecimal displays, for dividend, divider, quotient and remainder.

Here's the partially wired base board:

And here's the final base board:

A lot of care was taken to test everything for correct operation during construction of the various boards: the twelve discrete LEDs were included to give some diagnostic capability. In the completed divider, if the yellow LED is unlit, the red LEDs show a binary representation of the remainder (this can be seen for the partially wired board above: 555 (hex) = 10101010101 (binary). These sets of twelve LEDs are also included in each of the five (identical) stacked-up boards, allowing some useful testing of each board in isolation.

The four 15-way D-sub connectors are for the dividend, divisor, quotient and remainder, respectively. Interconnects to the stacked-up boards are via the miniature terminal blocks (0.1 inch spacing type).