One shall not plug 220V in the secondary circuit of a 220-12V transformer.
Not a good idea. Like at all. Magic smoke coming from a cable is not that magic…
(The thin cable turned into a fuse, and may have save more than a small transformer…)
At least, I learned my lesson and made a circuit breaker protected plug to test further projects…
Sam was kind enough to give me a 3 x splashback when I went to the museum a few months ago. Finally built it and after correcting a few minor issues it still wasn’t working. I did some very diligent error checking to figure out -12V wasn’t getting to the opAmp.
Regret to inform I am Idiot and apparently mangled the new power cable on my test rig and, ironically, didn’t test it
Build the cable tester, it’s worth it’s weight in fiberglass…
As said by others, a cable tester is a nice tool. Have a look at the one I’m using whenever I make a new cable:
That’s really neat . I usually just stick an unused socket onto the plug and use a multimeter on the pins. I don’t know why I didn’t test this one !
Ugh I sent all day working up panels out of scrap plastic but when I started making hokes for components they shattered. The plastic is far too britle. If I wasn’t off my head with covid I’d be furious.
Masking tape and taking it slow are your friends.
what christian said, plus making pilot holes.
Could always bend the support in a bit? Saves it incase the tape wears through =D
Overlapping courtyards? DRC should catch that. Or… does it?
Oooh. No, it doesn’t, because each has only a front courtyard, and when one is on one side and one is on the other, they don’t overlap!
Yes, and I also sometimes ignore overlapping courtyards because there is so little space on the PCB 
bad practice, I know, but sometimes it can save me a bit of a headache 
Nah, it’s not bad practice. It’s good practice to check and to decide whether it’s a real problem or not. Sometimes the courtyards are just bigger than they need to be.
And sometimes not but there’s a workaround.
thats one of the new modules that you are still " working around " ? .
That’s the Barton full wave rectifier.
I sometimes ask myself, “Why do I bother with polarity reversal diodes? I use box headers. I check my cables. What could go wrong?”
Today I made a little modified bus board for my workbench. I tested it, looked good; the LEDs on it lit up as they should.
Tonight three VCOs were saved from oblivion by their polarity reversal diodes…
“How could the bus board be wrong? The LEDs wouldn’t light up if it were wrong! … Unless the LEDs were backwards too…”
one of the few things i do religiously is to check any power stuff I build with the meter. but thats probly cos half the time they don’t work
When creating noyce PCBs, after reading messages for shorts and so, be reminded to check what you write on the PCB (like resistor values). Your future you is dumb and will follow exactly what’s written.
Inverting resistors caused:
I guess I am lucky, I got no magic smoke so far.
I use custom footprints that have both the reference and value shown, so I don’t have to “write on the PCB” so much. But they don’t always save me from scenarios like:
“Right, need to rotate C1”
“Now I want the caps closer together”
“But now the refs and values are illegible, got to move them”
“Perfect! … Wait, why isn’t this thing working?”
[Having failed to notice that nearly invisible dark blue line…]
Added: Huh. I just went into Preferences > PCB Editor > Colors > Anchors:
and clicked “Reset to Default”:
and now it’s
I was a dumbass if I changed that color from magenta to dark blue, but I don’t think I did, I think they must have changed the default…
Added more: They certainly did!
IIRC the oldest entry on the KiCad bug/feature request tracker is to specify a footprint as being non-polarised. That means you’ll be able to place a resistor either way round to avoid having to flip it and fudge about with the reference designators on the silkscreen. Eventually.
edit: yes, I did remember correctly!
