I didn't learn PCB design out of curiosity. I learned it because the published design files for the project's drive board turned out to be missing their ground connections, the author wasn't answering email, and waiting with no fallback was not a plan. The full detective story is §M6. This chapter is about what that emergency did for me, which was to hand me the single best KiCad assignment a beginner can get.
Same board, ground done right
The task was specific. Re-create the drive board's schematic in KiCad, from the author's published schematic, with one deliberate difference, a ground scheme that actually connected. Then lay out the PCB.
Total time from never having opened KiCad to a finished schematic and a partial layout was about 4 to 6 solid hours (Estimated). I want to be honest about that number in both directions. It's small, which says something encouraging about modern KiCad and about learning under pressure. It's also solid hours (focused, with a real board on the line), and the layout was only partway done when events overtook it (more below). The schematic was never fabbed and never bench-tested, so I can't call it verified, only finished. But the takeaway stands. The distance from zero to a complete schematic of a real mixed-signal board is an evening or two, not a semester.
Re-drawing someone else's schematic turned out to be the fastest possible tutorial, for a reason I didn't expect. You cannot re-draw what you haven't actually read. Skimming a schematic feels like understanding, but re-creating it symbol by symbol, pin by pin, is a line-by-line interrogation. By the end I didn't just have a copy of the drive board's schematic. I understood the signal chain well enough to debug it later, which is worth more than the file.
The hard part was knowing which line is which
The famous beginner walls in PCB design are footprints and DRC errors. Those weren't my wall. My wall was the connectors and terminals: positive, negative, ground, times every component, times every wire. Keeping track of which line is which terminal across a whole schematic was the genuinely confusing part, and my coping mechanism, color-coding each line by hand, was mind-numbingly tedious. At the time I was sure the software was missing a feature. The software was not missing a feature.
What I know now, and what April-me is allowed to hear, is that the underlying skill isn't visual tracking at all. It's net thinking. Every wire belongs to a named electrical net, KiCad has net labels and net highlighting for exactly this, and the moment you name your nets (+15V, −15V, GND, DA1_OUT) instead of following lines with your eyes, the tracking problem mostly dissolves (general KiCad knowledge, which I found later, the hard way). My hand-coloring phase was me manually doing what net labels do, and the tedium was a sign that I was missing the abstraction.
Deliverables
The redesign lives in the project as dac_board_v2/: the schematic (dac_board_v2.kicad_sch), the partial layout (dac_board_v2.kicad_pcb), a placement-coordinates file, and REFERENCE_MAPPING_kicad_to_liao.md, a table mapping my auto-assigned designators to the original board's, written so the two schematics could be cross-read.
The race ended before the finish line
While the layout was in progress, the original author finally replied, with corrected design files (§M6 has the timeline). At that moment my schematic was done and my layout was partial. The decision was easy and a little anticlimactic. Fab from the author's corrected files, which carried his layout exactly, and shelve my redesign unfabbed [project CLAUDE.md §2].
So the board I spent those hours designing was never manufactured. And it still paid for itself twice over. As insurance, it gave the project a fallback path during the silent weeks instead of a dead stop. And as a reference, my KiCad schematic became the net-level map of the circuit during bring-up and debugging, something I could search, highlight, and interrogate, which the original PDF schematic could never be. (The designator mapping file became obsolete. The fabbed board used the original designators on its silkscreen, so my cross-reference table outlived its purpose within a week. Documentation has a shelf life.)
The board I didn't build taught me more than most things I did build.
Advice for beginners
Re-draw a real schematic you need. It beats every tutorial. Name your nets on day one, because the urge to color-code by hand is the missing-abstraction alarm. A finished schematic with a partial layout is not a failure. It's most of the value. And design work that gets overtaken by events isn't wasted if it de-risked the wait and left you understanding the circuit.
Summary of the three tools
Three tools, learned in three months, all for one bench: the scope taught me to see signals, the iron taught me to build the board, and KiCad taught me to understand it well enough to fix. §M6 is where all three got their real exam. That was the day the drive board's published files turned out to be broken, and a beginner with a scope, an iron, and a half-learned CAD package had to deal with it.