Aidan Lakshman

Aidan Lakshman

Doctoral Candidate, University of Pittsburgh School of Medicine

64th02 Computer, Part 2

1 minute read

Published:

I finally got my shipment of resistors and soldering wicks, so it’s time to complete the hardware build for this computer! Unfortunately header pins are numerous, and soldering wicks aren’t quite as effective as I had hoped at removing solder. Fortunately I had plenty of extra parts, and PCBway’s minimum PCB shipment is five boards, so I decided to start over from scratch.

This time, I only had one issue: my variety pack of resistors didn’t come with a 3.3kΩ resistor. What it did have, however, were plenty of 1kΩ resistors and 2.2kΩ resistors. 3.2kΩ with a tolerance of 5% is 3,040-3,460Ω, which is close enough to 3.3kΩ to make it work. I wired the resistors in series and put solder on the connection, forming a functional (albeit relatively messy) connection.

After that, all that was left was soldering in new pieces and sockets, this time with the pins in the right orientation! I also paid a little closer attention to the capacitors I soldered in–the writing is so tiny, it’s easy to mistake a 103M for a 104M. On this iteration, we have correct capacitors in all the sockets, plus a nice new blue LED!

All that’s left is to pop in the ICs, and voila.

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