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by meta_AU 2725 days ago
Making test points for all your testable functions and aligning them to a stripboard really simplified making a testing jig. You can solder some pogo pins to the strip board and just press each board to your jig to program/test it.

Also, I've found renumbering passives to keep the same values in contiguous groups to simplify hand prototyping. You end up having dozens of 0.1uF for example and it's nice to knock them all out instead of switching between different components
2 comments
DominoTree 2725 days ago
For hand assembly I usually break out all of the components into little iFixIt project trays and print out labels that correspond to the board, but when there are a bunch of components with the same value, I just put the value on the label instead, and use highlighters on to point them out on printouts so I don't spend forever hunting where to place them. Then, I just go one by one down each spot in each tray until I've populated a board, then I throw it in the oven and start on the next.

https://pbs.twimg.com/media/DvIU0gSXQAE883Y.jpg:large

https://pbs.twimg.com/media/Dv2KXBuW0AAQY5c.jpg:large

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jacquesm 2725 days ago
That is a nice idea, thank you!
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exmadscientist 2725 days ago
When numbering components, my favorite approach is to group designators by subcircuit. That means one circuit (say, an op-amp circuit) might have U41, R41-R46, C41-C43, and Q41; the next circuit would have U51-U52, R51-54, C51-59, and L51. You get the idea. That way, not only is PCB to schematic lookup made easy (and I find that's the one most in need of optimization), but on a good layout, a subcircuit will be laid out together, so you get PCB designator locality for free! The exception to this is decoupling capacitors; if I'm assembling by hand, I'll usually put them at the end of the list (so, continuing my previous example, they might be C60-C81, if there were only five subcircuits). I only bother with this for hand assembly, though; robots don't care.
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stephen_g 2725 days ago
We do things a bit like that - we break things up in the schematic by page (between one and a couple of sub-circuits per page), and then the designator is page number plus a sequential ID. So you might have C405 (4th cap on page 4) or C847, etc.

We don’t print designators on silkscreen, so it’s not really a problem with the length (e.g when you get over 10 pages and have a five or more digit long designator. With a page that is subclassed you might have one like R1208B for example!)

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