Waiting on a few parts, boards otherwise done

SHORT A FEW INTEGRATED CIRCUITS AND CAPACITORS

I was missing a 74LS154 decoder (4 input to 16 output), a couple of 74LS07 buffers to drive LEDs, and a smattering of 74LS00 (quad NAND) and 74LS04 (hex inverter) parts. They are arriving from Digikey except the nearly obsolete 74LS154 which is coming from eBay. 

The design uses plenty of 47nf decoupling capacitors on the PCBs and I didn't have a large enough supply. They will be arriving by this weekend and get installed. 

CONNECTORS, CABLES AND SWITCHES ON ORDER

The front panel uses fifteen paddle switches, five of them momentary contact type. In addition, there are plenty of cables running between boards and to the rear panel where the peripheral device connectors are placed. I ordered these from AliExpress and hope they won't take too long to arrive from China. Similarly, the PCB sockets that fit on the motherboard were ordered from AliExpress. 

BOARDS PUT TOGETHER EXCEPT FOR THE MISSING PARTS MENTIONED ABOVE

As you can see, the boards are mostly soldered together and just waiting for final parts before I can begin testing. 


The boards on the top row are, from left to right, the accumulator, the memory and the input output transfer PCBs. The middle row are, from left to right, instruction decoder, program counter/adder and timing PCBs. The bottom row has the motherboard (sans connectors) on the left and the front panel (sans switches) on the right. Blue tape covers the spots for the ten missing ICs. 

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